In the light of poor salt tolerance and difficulty to improve washing oil efficiency of the polymers used in oil fields, a kind of salt tolerance copolymer with surface activity，called GL, was synthesized and the characteristics of GL were evaluated under specific reservoir condition of Daqing oil field. The results demonstrated that, when the solution concentrations were between 250 mg/L and 1500 mg/L and the salinity was 2400 mg/L and the temperature were 45℃, the viscosity of GL solutions were higher than that of HPAM solutions. Although the viscosity of the two kinds of polymer solutions at the concentration of 1000 mg/L decreased with the increase of the salinity, the viscosity of GL solution was almost 20 mPa·s higher than that of HPAM solution. The water separation ratio of the emulsion obtained with GL solution at the concentration of 1000 mg/L and the crude oil was lower, being of about 50%, while that of HPAM solution at the same concentration reached 95% quickly. The oil displacement experiment results indicated that based on the water flood, the oil recovery of the GL solution was 4.0% higher than that of HPAM solution at the same concentration (1000 mg/L); the oil recovery of the GL solution with 2.6% higher than that of HPAM solution at the same viscosity (62 mPa·s )with same viscosity.