Sodium benzoate of p-acrylamide (a) was synthesized by amine hydrolysis reaction and neutralization reaction，redox initiator of ammonium persulfate /sodium bisulfite，a binary copolymer (b) was synthesized with sodium benzoate of p-acrylamide and methacryloxyethyl trimethyl ammonium chloride as monomers.Using Yanchang heavy oil simulated heavy oil emulsion to evaluate the performance of homemade tetrapolymers demulsifier．The flocculation and oil removal performances of binary copolymer were also investigated.The results showed that under the condition of demulsification temperature 70℃，demulsification dosage 110 mg /L ，demulsification time 2 h,the dehydration was reached up 92.04%,the supernatant transparency was up to 98.6% and the flocculation time was 9 s，at room temperature and copolymer dosage of 12 mg/L and the oil removal rate of copolymer was 94.5%,under the conditions of 30 mg/L copolymer dosage,50℃ and 7 h. The flocculation-demulsification performance of self made polymer was superior to BQ-05、SP-169 and PAM、PDMC.