We　report　on　and　discuss　the　effects　of　intermittent　starvation　on　the　operation　of　the　simultaneous　partial　nitrification,　ANAMMOX,　and　denitrification　(SNAD)　process.　The　SNAD　process　was　carried　out　in　a　sequencing　batch　reactor　(SBR)　at　room　temperature　(22±3),　and　the　intermittent　starvation　was　achieved　by　periodically　extending　the　hydraulic　retention　time　(HRT)　of　the　system.　The　results　showed　that　after　the　operation　of　intermittent　starvation,　the　NO3--N　concentration　at　the　end　of　the　aerobic　phase　decreased　to　8.72　mg•L-1　and　the　NO2-　accumulation　percentage　reached　83.18%,　which　indicated　that　the　nitrite　oxidizing　bacteria　(NOB)　activity　was　effectively　inhibited　and　that　the　nitritation　performance　improved.　After　the　operation　of　the　intermittent　starvation,　the　ratio　of　NO2-　to　NH4+-N　at　the　end　of　the　aerobic　phase　was　adjusted　to　provide　more　suitable　substrates　for　the　subsequent　ANAMMOX　process,　such　that　the　concentration　of　NH4+-N　in　the　effluent　fell　below　1.0　mg•L-1.　At　the　same　time,　due　to　the　decrease　of　the　NO3-　concentration,　the　total　N　removal　rate　reached　92.07%,　which　indicated　that　the　treatment　performance　improved.　By　determining　the　activity　of　the　functional　bacteria,　we　found　that　the　main　reason　for　the　improvement　in　the　nitritation　performance　after　starvation　was　that　the　decay　rate　of　the　ammonia　oxidizing　bacteria　(AOB)　activity　during　the　starvation　period　was　lower　than　of　the　decay　rate　of　the　NOB　activity,　and　that　the　recovery　rate　of　the　AOB　activity　during　the　recovery　period　was　significantly　higher　than　that　of　the　NOB.　©　2020,　Science　Press.　All　right　reserved.