Through the study on interfacial tension，emulsifying ability，adsorptive property，compatibility，decompression and augmented injection capacity，and oil displacement experiment，the performance of anionic-nonionic surfactant（named SKDAS） was evaluated. The results showed that the final interfacial tension between，0.1%—0.9% SKDAS and the oil of Ansai oilfield maintained to 10^-3 mN/m order of magnitude. The interfacial tension of 0.5% SKDAS could reach 10^-3 mN/m order of magnitude when the salinity was 1×10⁴—9×10⁴ mg/L，showing good salinity tolerance. SKDAS had strong emulsifying ability for crude oil. The higher concentration，the better emulsifying property was. The adsorption capacity of SKDAS solution in oil sands was 0.11— 0.14 mg/g when the mass fraction of SKDAS was 0.1%—0.5%。The compatibility between SKDAS and clear water or produced water of Ansai oilfield was good. When the mass fraction of SKDAS increased from 0.3% to 0.7%，SKDAS flooding could improve the oil recovery 10.41% —12.84% based on water flooding system，which could satisfy the requirement of surfactant oil displacement in Ansai oilfield.