Dealing with the polymer flooding sewage and injection to the stratum in LD10-1 oilfield is the important guarantee for developing of the oilfield, using a nonionic purifying agent BHQ-402, the treatment effect of the dosage, stirring speed, stirring time and other factors, were investigated. The results showed that, when the BHQ-402 was diluted to mass fraction of 1% with fresh water, the degreasing and cleansing effect was good at the BHQ-402 amount of 500 mg/L, pharmacy reaction of 200—400 r/min, and stirring time of 2—3 min. Oil removal rate was up to 83.69%, and turbidity removal rate was as high as 92.74%.When the BHQ-402 was first dissolved with ethyl alcohol and then diluted to mass fraction of 1% with fresh water, when the BHQ-402 amount was 200 mg/L, stirring speed was 400 r/min and stirring time was 3 min, the degreasing rate was greater than or equal to 87%, and the turbid rate was greater than or equal to 92%. The BHQ-402 addition amount was less, while the treated water quality indicators were increased greatly.