SBR　reactors　R1　and　R2　were　used　to　inoculate　activated　sludge　from　a　sewage　treatment　plant,　and　domestic　sewage　was　used　as　the　influent.　The　operation　was　carried　out　using　a　single　and　multiple　influent-aeration　operation　strategy,　respectively,　and　the　particle　size　change　and　removal　effect　during　the　operation　was　studied.　The　results　show　that　R1　and　R2　successfully　achieved　sludge　granulation　after　56　days　and　39　days　of　operation,　respectively.　The　concentrations　(mg•L-1)　of　chemical　oxygen　demand,　total　nitrogen,　and　total　phosphorus　(TP)　in　the　effluent　of　R1　and　R2　after　stable　operation　were　29.7,　13.7,　0.31,　19.2,　8.1,　and　0.37,　respectively.　The　removal　rates　were　respectively　87.7%,　75.6%,　95.1%,　and　90.1%,　85.6%,　and　94.2%,　and　the　average　particle　size　of　the　particles　reached　740　μm　for　R1　and　791　μm　for　R2.　The　results　showed　that　for　the　same　running　time,　the　effluent　NO3--N　concentration　and　TP　concentration　in　R2　were　lower　than　those　in　R1.　In　the　later　stage　of　operation,　the　ratio　of　denitrifying　phosphorus-accumulating　organisms　(DPAO)　to　total　phosphorus-accumulating　organisms　(PAOs)　in　R1　and　R2　increased　from　an　initial　11.17%　to　25.47%　and　34.08%,　respectively.　Compared　with　the　one　influent-aeration　operation　strategy,　the　multiple　influent-aeration　operation　strategy　had　a　lower　concentration　of　NO3--N　in　the　initial　stage　of　the　startup,　the　PAOs　received　less　impact,　the　DPAO　enrichment　was　better,　the　phosphorus　removal　performance　was　better,　and　it　helped　to　form　aerobic　granular　sludge.　©　2020,　Science　Press.　All　right　reserved.