A type of betaine gemini surfactant was synthesized by two-step reaction with N- (3-dimethylaminopropyl) oleoylamide, 3-chloro-2-hydroxypropanesulfonate and 1,4-dibromobutane as main raw material. The structure of the product was characterized by fourier transform infrared spectroscopy and 1H nuclear magnetic resonance spectrum, the surface tension curve and related parameters were acquired by surface tension measurements. The surface tension of oleyl amidopropyl hydroxysultaine (B18) and gemini surfactants (B18-4-18) at different concentrations were measured. The experimental results showed that the structure of the synthesized compounds was in conformity with the expected structure of surfactant. The critical micelle concentration of B18 was 3.5914?0-6mol/L, the corresponding surface tension was 36.2155mN/m. The critical micelle concentration of B18-4-18 was 3.3986?0-6 mol/L, the corresponding surface tension was 34.6464mN/m at 25℃. The liquid carrying rate of B18 and B18-4-18 can reach 87% and 92% in water respectively. The liquid carrying rate of B18 and B18-4-18 can reach 82% and 84% in mineralized water with high salinity of 150 g/ L. The liquid carrying rate of B18 and B18-4-18 can reach 64% and 67% at 10% condensate oil.