Using polyoxyethylene lauryl ether and maleic anhydride as the main raw materials, a high surface activity gemini surfactant CAPM was synthesized, and the structure of CAPM was characterized by IR. The surface tension and oil/water interface tension were investigateded and the core displacement experiments were conducted with authentic sandstone microscopic model. The results showed that the surfactant CAPM could make surface tension of water reduce to 27.08 mN/m and the critical micelle concentration was about 0.163 g/L. The interface tension between the crude oil and CAPM solution could be reduced to 10-3 mN/m, which is suitable for enhancement of oil recovery. The core displacement experiments showed that the CAPM solution could displace the oil in the sandstone effectively.