A demulsifier DW1 was prepared by emulsion copolymerization.The demulsifier DW1 was characterized by FT?IR,GPC,¹H?NMR,¹³C?NMR and particle size analysis.The demulsification experiment using DW1 as demulsification system was carried out with Xinjiang sludge as the target treatment object,and the sludge before and after treatment was analyzed by sem.The results showed that the synthetic demulsifier DW1 had M_w of 13.9×10⁵ and M_n of 8×10⁵,molecular weight distribution index of 1.73,D₅₀ of 26.00 μm,average particle size of 25.00 μm,non?uniform particle size distribution,and good stability of DW1.The demulsification experiment shows that the oil removal rate of DW1 on a Xinjiang oil field can reach 99.55%.