Separating NDPAOs from the continuous flow double sludge nitrosation denitrifying phosphorus removal system, purifying and preliminary identifying them, discussing the effect of NO2--N concentration on the performance of denitrifying phosphorus accumulating of NDPAOs by the way of pure training. The results showed that the identified organism Veillonella could treat NO2--N as electronic receptors when the NO2--N concentration was 60mg/L; when the NO2--N concentration raised to 65mg/L, phosphorus accumulating was not normal; the denitrifying was abnormal while the NO2--N concentration further raised to 70mg/L; when the NO2--N concentration was 80mg/L, characteristics of phosphorus uptake and denitrifying had suffered serious inhibition.