Understanding　the　origin　of　fine　particulate　matter　is　essential　to　proposing　proper　strategies　for　heavy　haze　mitigation　in　Shanghai,　China.　In　this　study　we　used　the　Particulate　Matter　Source　Apportionment　Technology　in　Comprehensive　Air　Quality　Model　with　Extensions　to　quantify　the　impacts　of　emissions　on　the　concentrations　of　fine　particulate　matter　(PM2.5)　and　its　important　components　in　Shanghai　during　heavy　haze　episodes　in　late　autumn　(6-22　November　2010).　The　factors　considered　here　are　regions　of　Shanghai　and　its　surrounding　areas,　long-range　regional　transport,　and　different　local　emission　categories.　The　results　indicate　that　industrial　process　is　the　dominant　local　contributor　to　total　PM2.5　mass　in　the　whole　city　except　that　at　the　urban　center　vehicle　emission　contributes　slightly　more.　In　addition,　industrial　process　and　vehicle　emission　are　the　major　local　contributors　for　nitrate　in　Shanghai,　although　at　urban　core　the　contribution　from　vehicle　emission　is　remarkably　larger.　Generally,　both　local　contribution　and　regional　transport　contribution　could　dominate　a　severe　haze　event　in　late　autumn.　However,　the　dominant　contributor　could　either　be　local　emission　or　regional　transport,　usually　depending　on　the　meteorological　conditions.　Therefore,　particular　attentions　should　be　paid　to　the　emission　control　in　the　upwind　adjacent　provinces,　as　well　as　in　local　areas,　for　developing　effective　strategies　to　reduce　PM2.5　pollution　in　Shanghai.