Hebei　has　been　recognized　as　one　of　the　most　polluted　provinces　in　China,　characterized　by　extremely　high　concentrations　of　fine　particulate　matter　(PM2.5)　in　many　of　its　cities,　especially　those　located　in　the　southern　area　of　the　province　and　highly　potentially　northward　transported　to　Beijing.　Source　apportionment　of　PM2.5　is　the　basis　and　prerequisite　of　an　effective　control　strategy.　In　this　study,　the　Mesoscale　Modeling　System　Generation　5　(MM5)　and　the　Models-3/Community　Multiscale　Air　Quality　(CMAQ)　modeling　system　are　applied　to　East　Asia　and　North　China　at　36-　and　12-km　horizontal　grid　resolutions,　and　the　source　apportionment　of　PM2.5　in　the　three　top　polluted　cities　in　Hebei,　i.e.,　Shijiazhuang,　Xingtai,　and　Handan,　is　performed　using　the　Brute-Force　method.　It　is　concluded　that　the　regional　source　contributions　to　PM2.5　are　27.9%　in　Shijiazhuang,　46.6%　in　Xingtai,　and　40.4%　in　Handan.　The　major　local　contributors　are　industrial,　domestic　and　agricultural　sources　in　all　the　three　cities　with　the　contributions　of　39.8%,　15.8%,　and　10.6%　in　Shijiazhuang,　30.5%,　13.6%,　and　6.9%　in　Xingtai,　35.9%,　13.5%,　and　6.2%　in　Handan,　respectively.　As　to　the　secondary　aerosols　of　sulfate　(SO42-),　nitrate　(NO3-),　and　ammonium　(NH4+)　in　PM2.5,　which　are　important　chemical　species　in　PM2.5　(about　30-40%　in　PM2.5)　and　cannot　be　further　apportioned　by　receptor　models,　the　regional　source　contributions　to　the　total　concentrations　of　SO42-,　NO3-,　and　NH4+　are　40.9%,　62.0%,　and　59.1%　in　Shijiazhuang,　Xingtai,　and　Handan,　respectively.　The　local　industrial,　domestic　and　agricultural　contributions　to　those　are　23.7%,　6.6%,　and　29.8%　in　total　in　Shijiazhuang,　17.5%,　5.0%,　and　17.7%　in　Xingtai,　and　20.6%,　4.8%,　and　17.8%　in　Handan,　respectively.　The　regional　joint　controls　of　air　pollution　are　more　important　in　Xingtai　and　Handan　than　in　Shijiazhuang,　and　the　emission　controls　of　agricultural　sources　need　to　be　further　considered　in　the　future　policy.　(C)　2015　Elsevier　Ltd.　All　rights　reserved.