The　Potential　Source　Contribution　Function　(PSCF)　method　was　applied　to　identify　the　potential　pollution　source　areas　of　PM2.5　in　three　typical　cities　including　Beijing,　Tangshan　and　Shijiazhuang　in　autumn　and　winter　of　2018.　A　meteorology-air　quality　coupling　model　system　(WRF-CAMx)　and　the　method　of　transport　flux　calculation　were　applied　to　investigate　the　transmission　contribution　of　PM2.5　from　the　surrounding　provinces,　the　transport　pathway　of　PM2.5　in　three　typical　cities　and　the　vertical　distribution　characteristics　of　the　net　transmission　flux　of　PM2.5.　The　results　indicate　that　high　values　of　PSCF　in　autumn　and　winter　were　mainly　concentrated　in　the　south　of　Hebei,　the　northeast　of　Henan　and　the　central　and　eastern　parts　of　Shanxi.　Local　emission　sources　were　the　predominant　contributor　(51.78%~68.40%)　to　PM2.5　in　winter　and　autumn,　followed　by　the　external　regions　(31.60%~48.22%),　and　varied　between　two　seasons.　The　contribution　fluctuated　in　different　seasons.　The　adjacent　cities　mainly　export　PM2.5　to　Beijing　and　Shijiazhuang,　and　Tangshan　mainly　export　PM2.5　to　the　adjacent　cities,　with　the　largest　PM2.5　net　fluxes　mainly　occurred　at　0~50m,　and　the　net　fluxes　value　is　-99.47t/d　during　the　whole　study　period.　Moreover,　one　important　transport　pathways　were　identified:　the　southwest-northeast　pathway.　©　2021,　Editorial　Board　of　China　Environmental　Science.　All　right　reserved.