In　order　to　achieve　simultaneous　nitrogen　and　phosphorus　removal　in　low-C/N　urban　sewage,　a　sequencing　batch　reactor　(SBR)　was　operated　in　anaerobic/aerobic　(A/O)　mode.　Keeping　the　total　aeration　volume　at　900　L,　the　aeration　strategy　was　adjusted.　The　uniform　aeration　of　2.81　L•(h•L)-1　was　changed　to　＇high/low　aeration＇　with　high　strength　4.22　L•(h•L)-1before　low　strength　1.88　L•(h•L)-1,　and　＇low/high　aeration＇　with　low　strength　1.88　L•(h•L)-1　before　high　strength　4.22　L•(h•L)-1.　The　experiment　investigated　the　nitrogen　and　phosphorus　removal　performance　and　sludge　characteristics　of　the　system　under　different　aeration　strategies.　The　results　showed　that　the　nitrogen　and　phosphorus　removal　performances　of　the　system　under　high/low　aeration　were　the　best.　The　effluent　concentrations　of　NH4+-N,　NO2--N,　NO3--N,　and　TP　were　0,　0.15,　8.12,　and　0.04　mg•L-1,　respectively.　The　removal　rates　of　total　nitrogen　(TN)　and　total　phosphorus　(TP)　were　as　high　as　78.33%　and　99.19%,　respectively.　Simultaneous　nitrification　endogenous　denitrification　(SNED)　was　clear,　with　the　SNED　ratio　at　77.08%.　Compared　with　uniform　aeration,　the　system　nitrification　rate　and　denitrification　rate　increased,　and　the　denitrification　rate　reached　14.33　mg•(g•h)-1,　which　was　the　maximum　value　during　the　whole　operation;　the　solidity,　sedimentation　performance,　and　stability　of　granular　sludge　were　improved,　and　the　sludge　volume　index　(SVI)　was　23.49　mL•g-1.　After　adjusting　the　aeration　strategy　to　low/high　aeration,　the　nitrogen　and　phosphorus　removal　performance　of　the　system　deteriorated,　and　the　removal　rates　of　TN　and　TP　were　reduced　to　51.26%　and　58.32%,　respectively.　However,　the　system　had　the　best　nitrification　performance　with　ammonia　oxidation　rate　and　nitrate　production　rate　at　14.92　mg•(g•h)-1and　7.50　mg•(g•h)-1,　respectively,　which　were　their　maximum　values　during　the　whole　operation.　Simultaneously,　the　filamentous　bacteria　in　the　granular　sludge　multiplied,　the　granular　structure　became　loose,　the　sedimentation　and　stability　all　worsened,　and　the　SVI　rose　to　40.76　mL•g-1.　©　2019,　Science　Press.　All　right　reserved.