<?xml version="1.0" encoding="US-ASCII"?>
<!--XBRL Document Created with WebFilings-->
<!-- -->
<xsd:schema attributeFormDefault="unqualified" elementFormDefault="qualified" targetNamespace="http://www.mercuryinsurance.com/20120930" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:mcy="http://www.mercuryinsurance.com/20120930" xmlns:nonnum="http://www.xbrl.org/dtr/type/non-numeric" xmlns:num="http://www.xbrl.org/dtr/type/numeric" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <xsd:import namespace="http://fasb.org/us-gaap/2012-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd" />
  <xsd:import namespace="http://fasb.org/us-roles/2012-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2012/elts/us-roles-2012-01-31.xsd" />
  <xsd:import namespace="http://fasb.org/us-types/2012-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2012/elts/us-types-2012-01-31.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2009/arcrole/fact-explanatoryFact" schemaLocation="http://www.xbrl.org/lrr/arcrole/factExplanatory-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2009/role/negated" schemaLocation="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2009/role/net" schemaLocation="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/dtr/type/non-numeric" schemaLocation="http://www.xbrl.org/dtr/type/nonNumeric-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/dtr/type/numeric" schemaLocation="http://www.xbrl.org/dtr/type/numeric-2009-12-16.xsd" />
  <xsd:import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/country/2012-01-31" schemaLocation="http://xbrl.sec.gov/country/2012/country-2012-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/currency/2012-01-31" schemaLocation="http://xbrl.sec.gov/currency/2012/currency-2012-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/dei/2012-01-31" schemaLocation="http://xbrl.sec.gov/dei/2012/dei-2012-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/exch/2012-01-31" schemaLocation="http://xbrl.sec.gov/exch/2012/exch-2012-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/invest/2012-01-31" schemaLocation="http://xbrl.sec.gov/invest/2012/invest-2012-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/naics/2011-01-31" schemaLocation="http://xbrl.sec.gov/naics/2011/naics-2011-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/sic/2011-01-31" schemaLocation="http://xbrl.sec.gov/sic/2011/sic-2011-01-31.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/stpr/2011-01-31" schemaLocation="http://xbrl.sec.gov/stpr/2011/stpr-2011-01-31.xsd" />
  <xsd:annotation>
    <xsd:appinfo>
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="mcy-20120930_cal.xml" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:type="simple" />
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="mcy-20120930_def.xml" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:type="simple" />
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="mcy-20120930_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:type="simple" />
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="mcy-20120930_pre.xml" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:type="simple" />
      <link:roleType id="ConsolidatedBalanceSheets" roleURI="http://www.mercuryinsurance.com/role/ConsolidatedBalanceSheets">
        <link:definition>1001000 - Statement - Consolidated Balance Sheets</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ConsolidatedBalanceSheetsParenthetical" roleURI="http://www.mercuryinsurance.com/role/ConsolidatedBalanceSheetsParenthetical">
        <link:definition>1001501 - Statement - Consolidated Balance Sheets (Parenthetical)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ConsolidatedStatementsOfCashFlows" roleURI="http://www.mercuryinsurance.com/role/ConsolidatedStatementsOfCashFlows">
        <link:definition>1004000 - Statement - Consolidated Statements Of Cash Flows</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ConsolidatedStatementsOfComprehensiveLossIncome" roleURI="http://www.mercuryinsurance.com/role/ConsolidatedStatementsOfComprehensiveLossIncome">
        <link:definition>1003000 - Statement - Consolidated Statements Of Comprehensive (Loss) Income</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ConsolidatedStatementsOfOperations" roleURI="http://www.mercuryinsurance.com/role/ConsolidatedStatementsOfOperations">
        <link:definition>1002000 - Statement - Consolidated Statements Of Operations</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="Contingencies" roleURI="http://www.mercuryinsurance.com/role/Contingencies">
        <link:definition>2110100 - Disclosure - Contingencies</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeFinancialInstruments" roleURI="http://www.mercuryinsurance.com/role/DerivativeFinancialInstruments">
        <link:definition>2106100 - Disclosure - Derivative Financial Instruments</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeFinancialInstrumentsNarrativeDetails" roleURI="http://www.mercuryinsurance.com/role/DerivativeFinancialInstrumentsNarrativeDetails">
        <link:definition>2406402 - Disclosure - Derivative Financial Instruments (Narrative) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeFinancialInstrumentsScheduleOfDerivativeGainsAndLossesInConsolidatedStatementsOfOperationsDetails" roleURI="http://www.mercuryinsurance.com/role/DerivativeFinancialInstrumentsScheduleOfDerivativeGainsAndLossesInConsolidatedStatementsOfOperationsDetails">
        <link:definition>2406404 - Disclosure - Derivative Financial Instruments (Schedule Of Derivative Gains And Losses In The Consolidated Statements Of Operations) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeFinancialInstrumentsSummaryOfLocationAndAmountsOfDerivativeFairValuesInConsolidatedBalanceSheetsDetails" roleURI="http://www.mercuryinsurance.com/role/DerivativeFinancialInstrumentsSummaryOfLocationAndAmountsOfDerivativeFairValuesInConsolidatedBalanceSheetsDetails">
        <link:definition>2406403 - Disclosure - Derivative Financial Instruments (Summary Of Location And Amounts Of Derivative Fair Values In The Consolidated Balance Sheets) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DerivativeFinancialInstrumentsTables" roleURI="http://www.mercuryinsurance.com/role/DerivativeFinancialInstrumentsTables">
        <link:definition>2306301 - Disclosure - Derivative Financial Instruments (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="DocumentAndEntityInformation" roleURI="http://www.mercuryinsurance.com/role/DocumentAndEntityInformation">
        <link:definition>0001000 - Document - Document And Entity Information</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FairValueMeasurement" roleURI="http://www.mercuryinsurance.com/role/FairValueMeasurement">
        <link:definition>2105100 - Disclosure - Fair Value Measurement</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FairValueMeasurementNarrativeDetails" roleURI="http://www.mercuryinsurance.com/role/FairValueMeasurementNarrativeDetails">
        <link:definition>2405402 - Disclosure - Fair Value Measurement (Narrative) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FairValueMeasurementScheduleOfAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasisValuationTechniquesDetails" roleURI="http://www.mercuryinsurance.com/role/FairValueMeasurementScheduleOfAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasisValuationTechniquesDetails">
        <link:definition>2405403 - Disclosure - Fair Value Measurement (Schedule Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Valuation Techniques) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FairValueMeasurementSummaryOfChangesInFairValueOfLevel3FinancialAssetsAndFinancialLiabilitiesHeldAtFairValueDetails" roleURI="http://www.mercuryinsurance.com/role/FairValueMeasurementSummaryOfChangesInFairValueOfLevel3FinancialAssetsAndFinancialLiabilitiesHeldAtFairValueDetails">
        <link:definition>2405404 - Disclosure - Fair Value Measurement (Summary Of Changes In Fair Value Of Level 3 Financial Assets And Financial Liabilities Held At Fair Value) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FairValueMeasurementTables" roleURI="http://www.mercuryinsurance.com/role/FairValueMeasurementTables">
        <link:definition>2305301 - Disclosure - Fair Value Measurement (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FairValueOfFinancialInstruments" roleURI="http://www.mercuryinsurance.com/role/FairValueOfFinancialInstruments">
        <link:definition>2103100 - Disclosure - Fair Value of Financial Instruments</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FairValueOfFinancialInstrumentsEstimatedFairValuesOfFinancialInstrumentsDetails" roleURI="http://www.mercuryinsurance.com/role/FairValueOfFinancialInstrumentsEstimatedFairValuesOfFinancialInstrumentsDetails">
        <link:definition>2403403 - Disclosure - Fair Value of Financial Instruments (Estimated Fair Values Of Financial Instruments) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FairValueOfFinancialInstrumentsNarrativeDetails" roleURI="http://www.mercuryinsurance.com/role/FairValueOfFinancialInstrumentsNarrativeDetails">
        <link:definition>2403402 - Disclosure - Fair Value of Financial Instruments (Narrative) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FairValueOfFinancialInstrumentsTables" roleURI="http://www.mercuryinsurance.com/role/FairValueOfFinancialInstrumentsTables">
        <link:definition>2303301 - Disclosure - Fair Value of Financial Instruments (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FairValueOption" roleURI="http://www.mercuryinsurance.com/role/FairValueOption">
        <link:definition>2104100 - Disclosure - Fair Value Option</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FairValueOptionGainsAndLossesDueToChangesInFairValueOfInvestmentsDetails" roleURI="http://www.mercuryinsurance.com/role/FairValueOptionGainsAndLossesDueToChangesInFairValueOfInvestmentsDetails">
        <link:definition>2404402 - Disclosure - Fair Value Option (Gains And Losses Due To Changes In Fair Value Of Investments) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="FairValueOptionTables" roleURI="http://www.mercuryinsurance.com/role/FairValueOptionTables">
        <link:definition>2304301 - Disclosure - Fair Value Option (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="General" roleURI="http://www.mercuryinsurance.com/role/General">
        <link:definition>2101100 - Disclosure - General</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GeneralDetails" roleURI="http://www.mercuryinsurance.com/role/GeneralDetails">
        <link:definition>2401402 - Disclosure - General (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GeneralPolicy" roleURI="http://www.mercuryinsurance.com/role/GeneralPolicy">
        <link:definition>2201201 - Disclosure - General (Policy)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GoodwillAndOtherIntangibleAssets" roleURI="http://www.mercuryinsurance.com/role/GoodwillAndOtherIntangibleAssets">
        <link:definition>2107100 - Disclosure - Goodwill and Other Intangible Assets</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GoodwillAndOtherIntangibleAssetsNarrativeDetails" roleURI="http://www.mercuryinsurance.com/role/GoodwillAndOtherIntangibleAssetsNarrativeDetails">
        <link:definition>2407402 - Disclosure - Goodwill and Other Intangible Assets (Narrative) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GoodwillAndOtherIntangibleAssetsScheduleOfComponentsOfOtherIntangibleAssetsDetails" roleURI="http://www.mercuryinsurance.com/role/GoodwillAndOtherIntangibleAssetsScheduleOfComponentsOfOtherIntangibleAssetsDetails">
        <link:definition>2407403 - Disclosure - Goodwill and Other Intangible Assets (Schedule Of Components Of Other Intangible Assets) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GoodwillAndOtherIntangibleAssetsScheduleOfEstimatedFutureAmortizationExpenseRelatedToIntangibleAssetsDetails" roleURI="http://www.mercuryinsurance.com/role/GoodwillAndOtherIntangibleAssetsScheduleOfEstimatedFutureAmortizationExpenseRelatedToIntangibleAssetsDetails">
        <link:definition>2407404 - Disclosure - Goodwill and Other Intangible Assets (Schedule Of Estimated Future Amortization Expense Related To Intangible Assets) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="GoodwillAndOtherIntangibleAssetsTables" roleURI="http://www.mercuryinsurance.com/role/GoodwillAndOtherIntangibleAssetsTables">
        <link:definition>2307301 - Disclosure - Goodwill and Other Intangible Assets (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxes" roleURI="http://www.mercuryinsurance.com/role/IncomeTaxes">
        <link:definition>2109100 - Disclosure - Income Taxes</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="IncomeTaxesDetails" roleURI="http://www.mercuryinsurance.com/role/IncomeTaxesDetails">
        <link:definition>2409401 - Disclosure - Income Taxes (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="RecentlyIssuedAccountingStandards" roleURI="http://www.mercuryinsurance.com/role/RecentlyIssuedAccountingStandards">
        <link:definition>2102100 - Disclosure - Recently Issued Accounting Standards</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ShareBasedCompensation" roleURI="http://www.mercuryinsurance.com/role/ShareBasedCompensation">
        <link:definition>2108100 - Disclosure - Share-Based Compensation</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ShareBasedCompensationNarrativeDetails" roleURI="http://www.mercuryinsurance.com/role/ShareBasedCompensationNarrativeDetails">
        <link:definition>2408402 - Disclosure - Share-Based Compensation (Narrative) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ShareBasedCompensationScheduleOfPerformanceVestingRestrictedStockUnitsGrantedDetails" roleURI="http://www.mercuryinsurance.com/role/ShareBasedCompensationScheduleOfPerformanceVestingRestrictedStockUnitsGrantedDetails">
        <link:definition>2408403 - Disclosure - Share-Based Compensation (Schedule Of Performance Vesting Restricted Stock Units Granted) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="ShareBasedCompensationTables" roleURI="http://www.mercuryinsurance.com/role/ShareBasedCompensationTables">
        <link:definition>2308301 - Disclosure - Share-Based Compensation (Tables)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType id="SubsequentEvent" roleURI="http://www.mercuryinsurance.com/role/SubsequentEvent">
        <link:definition>2111100 - Disclosure - Subsequent Event</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
    </xsd:appinfo>
  </xsd:annotation>
  <xsd:element id="mcy_AmortizedCostOnFixedMaturityTradingInvestments" name="AmortizedCostOnFixedMaturityTradingInvestments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcy_AmountOfTotalLossesGainsForPeriodIncludedInEarningsAttributableToAssetsStillHeld" name="AmountOfTotalLossesGainsForPeriodIncludedInEarningsAttributableToAssetsStillHeld" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_BankOfAmericaMember" name="BankOfAmericaMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_CostEquitySecurityTradingInvestments" name="CostEquitySecurityTradingInvestments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcy_CostShortTermInvestments" name="CostShortTermInvestments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcy_CreditFacilityMember" name="CreditFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_DerivativeFinancialInstrumentsLineItems" name="DerivativeFinancialInstrumentsLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_DerivativeFinancialInstrumentsTable" name="DerivativeFinancialInstrumentsTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_DocumentAndEntityInformationAbstract" name="DocumentAndEntityInformationAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_EquityContractsFinancialInstrumentsLiabilitiesFairValueDisclosure" name="EquityContractsFinancialInstrumentsLiabilitiesFairValueDisclosure" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="mcy_EstimatedFairValuesOfFinancialInstrumentsTableTextBlock" name="EstimatedFairValuesOfFinancialInstrumentsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_FairValueAssetsMeasuredOnRecurringBasis" name="FairValueAssetsMeasuredOnRecurringBasis" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="mcy_FairValueLiabilitiesMeasuredOnRecurringBasis" name="FairValueLiabilitiesMeasuredOnRecurringBasis" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="mcy_FairValueMeasurementLineItems" name="FairValueMeasurementLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_FairValueMeasurementTable" name="FairValueMeasurementTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_FairValueOptionAbstract" name="FairValueOptionAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_FairValueQualitativeDisclosuresRelatedToElectionByEligibleItemOrGroupAxis" name="FairValueQualitativeDisclosuresRelatedToElectionByEligibleItemOrGroupAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_FairValueQualitativeDisclosuresRelatedToElectionByEligibleItemOrGroupDomain" name="FairValueQualitativeDisclosuresRelatedToElectionByEligibleItemOrGroupDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_FairValueTransfersBetweenLevelsOneTwoAndThreeAmount" name="FairValueTransfersBetweenLevelsOneTwoAndThreeAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_GeneralAbstract" name="GeneralAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_NetRealizedInvestmentGainsMember" name="NetRealizedInvestmentGainsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_NumberOfKnowledgeableOutsideSecurityBrokersConsultedToDetermineFairValue" name="NumberOfKnowledgeableOutsideSecurityBrokersConsultedToDetermineFairValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:positiveIntegerItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_OptionsGrantedPriorToTwoThousandEightMember" name="OptionsGrantedPriorToTwoThousandEightMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_OptionsGrantedSubsequentToJanuaryOneTwoThousandEightMember" name="OptionsGrantedSubsequentToJanuaryOneTwoThousandEightMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_PartnershipInterestInPrivateCreditFundMember" name="PartnershipInterestInPrivateCreditFundMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_PercentageOfLargestAmountOfTaxBenefitRealized" name="PercentageOfLargestAmountOfTaxBenefitRealized" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_PercentageOfSpecificUnadjustedBrokerQuotesObtained" name="PercentageOfSpecificUnadjustedBrokerQuotesObtained" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_PercentageOfUnadjustedFairValueObtained" name="PercentageOfUnadjustedFairValueObtained" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_PerformancePeriodOfRestrictedStockAndRestrictedStockUnits" name="PerformancePeriodOfRestrictedStockAndRestrictedStockUnits" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_PerformanceVestingRestrictedStockUnitsThreeYearPerformancePeriodEndingYears" name="PerformanceVestingRestrictedStockUnitsThreeYearPerformancePeriodEndingYears" nillable="true" substitutionGroup="xbrli:item" type="xbrli:gYearItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_PerformanceVestingRestrictedStockUnitsVestingSharesMaximum" name="PerformanceVestingRestrictedStockUnitsVestingSharesMaximum" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="mcy_ProceedsFromCallsOfAvailableForSaleSecuritiesEquity" name="ProceedsFromCallsOfAvailableForSaleSecuritiesEquity" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="mcy_ScheduleOfDerivativeGainsAndLossesInConsolidatedStatementsOfOperationsTableTextBlock" name="ScheduleOfDerivativeGainsAndLossesInConsolidatedStatementsOfOperationsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_SecuredNotesOneMember" name="SecuredNotesOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_SecuredNotesTwoMember" name="SecuredNotesTwoMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="mcy_UnionBankMember" name="UnionBankMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
</xsd:schema>
