Submicron　particle　(PM1)　pollution　has　received　increased　attention　in　recent　years;　however,　few　studies　have　focused　on　such　pollution　in　the　city　of　Shijiazhuang　(SJZ),　which　is　one　of　the　most　polluted　cities　in　the　world.　In　this　study,　we　conducted　an　intensive　simultaneous　sampling　of　PM1　and　PM2.5　in　autumn　2016,　in　order　to　explore　pollution　characteristics　and　sources　in　SJZ.　The　results　showed　that　the　average　mass　concentrations　of　PM1　and　PM2.5　were　70.51　g/m(3)　and　91.68　g/m(3),　respectively,　and　the　average　ratio　of　PM1/PM2.5　was　0.75.　Secondary　inorganic　aerosol　(SIA)　was　the　dominant　component　in　PM1　(35.9%)　and　PM2.5　(32.3%).　An　analysis　of　haze　episodes　found　that　SIA　had　a　significant　influence　on　PM1　pollution,　NH4+　promoted　the　formation　of　pollution,　and　SO42-　and　NO3-　presented　different　chemical　mechanisms.　Additionally,　the　results　of　source　apportionment　implied　that　secondary　source,　biomass　burning　and　coal　combustion,　traffic,　industry,　and　dust　were　the　major　pollution　sources　for　SJZ,　accounting　for　45.4%,　18.9%,　15.7%,　10.3%,　and　9.8%　of　PM1,　respectively,　and　for　42.4%,　18.8%,　12.2%,　10.2%,　and　16.4%　of　PM2.5,　respectively.　Southern　Hebei,　mid-eastern　Shanxi,　and　northern　Henan　were　the　major　contribution　regions　during　the　study　period.　Three　transport　pathways　of　pollutants　were　put　forward,　including　airflows　from　Shanxi　with　secondary　source,　airflows　from　the　central　Beijng-Tianjin-Hebei　region　with　fossil　fuel　burning　source,　and　airflows　from　the　southern　North　China　Plain　with　biomass　burning　source.　The　systematic　analysis　of　PM1　could　provide　scientific　support　for　the　creation　of　an　air　pollution　mitigation　policy　in　SJZ　and　similar　regions.