Abstract: The article compared the treatment effect of self-made phosphorus coagulant: NDH to dry distillation sewage of oil shale with that of the traditional coagulant: polymerization aluminium sulfate(PAS),iron trichloride(FC),polymerization chlorinates ferro-aluminum(PAFC),the self-made coagulant was quite obviously superior,and the experiment showed that its best process condition was: pH=9,self-restraint coagulant 0.18 g/L and Polyacrylamide(PAM)0.02 g/L,the oil content was reduced from 5910 mg/L to 474 mg/L,the oil removing rate was 91.4%;NH₃-N was reduced from 563 mg/L to 397 mg/L;chemical oxygen demand(COD_Cr) was reduced from 24064 mg/L to 632.5 mg/L,the elimination rate was 97.37%.