Abstract:under different salinity conditions, the viscosity of binary system changes amplitude, the interfacial tension is not the same degree of stability, while binary system directly affect the oil displacement effect, in order to solve this problem, to carry out laboratory experiments to determine the effects of different salinity on binary system.Resules show that salinity is above 3000mg/L, the viscosity change range decreases greatly with the increase of salinity, the salt resistance increases, and the surfactant concentration has little effect on the viscosity of the system. The salinity is above 3000mg/L, the interfacial tension decreased with increasing salinity, when the surfactant concentration is increased from 0.3% to 0.4%, the interfacial tension decreased slowly, can reach 10-2mN/ m magnitude, meet the actual needs of the fields.