Due　to　the　similarity　of　PM2.5　chemical　species　profiles　of　different　sources,　time　synchronization　of　source　contributions　and　the　uncertainties　of　source-oriented　models,　it　is　difficult　to　get　a　well-separated　and　relatively　accurate　PM2.5　source　apportionment　result,　especially　for　the　secondary　components,　when　only　one　method　was　applied.　A　new　PM2.5　source　apportionment　approach,　combining　the　receptor　models,　source-oriented　models　and　emission　inventory,　was　developed　in　this　study.　The　proposed　method　had　following　strengths:　(1)　it　could　identify　the　source　contributions　to　secondary　components;　(2)　target　(or　expected)　sources　were　optional;　(3)　mixed　sources　could　be　avoided.　The　new　approach　was　then　applied　in　two　typical　cities　in　North　China　-　Beijing　and　Tangshan,　based　on　intensive　PM2.5　observation　results　from　2011　to　2013.　The　source　apportionment　result　indicated　that　the　annual　average　contribution　to　PM2.5　in　Tangshan　was　7.4%,　21.5%,　7.6%,　18.0%,　14.5%,　10.9%　and　20.0%　for　power,　metallurgy,　cement,　coal　combustion,　vehicle,　dust　and　other　sources,　respectively;　the　annual　average　contribution　ratio　for　vehicle,　industry　and　industrial　coal　combustion,　residential　coal　combustion,　dust　and　other　sources　in　Beijing　was　31.5%,　22.9%,　10.6%,　14.5%　and　20.4%,　respectively.　Seasonal　variation　of　the　source　contributions　was　also　analyzed.　The　demonstration　results　showed　that　the　combined　method　was　feasible.　In　addition,　the　detailed　source　contribution　results　could　also　provide　scientific　support　for　making　effective　PM2.5　mitigation　strategy.