To　discuss　the　characteristics　of　effluent　organic　matter　(EfOM)　from　biologically　treated　sewage　effluent,　the　impact　of　pH　value　on　SBR　was　originally　evaluated　with　an　artificial　wastewater.　The　results　revealed　that　dissolved　organic　matter　(DOM)　from　SBR　was　greatly　influenced　by　pH　value.　When　pH　value　of　the　SBR　with　original　pH　of　6.5　was　decreased　to　6.0,　DOC　of　its　effluent　gradually　increased　from　its　original　4.0　mg　x　L(-1).　Further　increasing　pH　can　alleviate　this　increase.　For　the　SBR　with　original　pH　of　8.0,　DOC　of　effluent　decreased　rapidly　from　its　original　4.0　mg　x　L(-1)　to　2　mg　x　L(-1),　while　further　decreasing　pH　to　6.5　did　not　affected　this.　Tannin　and　soluble　microbial　products　(SMPs)　including　protein,　carbohydrate　and　DNA　consist　to　the　main　part　of　DOM　in　the　sewage　effluent.　The　pH　value　had　a　long-term　impact　on　the　formation　of　SMPs.　Decreasing　pH　will　result　in　its　gradual　increase.　The　impact　of　pH　value　on　anaerobic　process　dominated　the　DOM　degradation　during　the　operation　period.　Higher　pH　value　was　helpful　for　the　degradation　of　DOM.