To clarify primary or secondary effect of emulsion and interfacial tension on remaining oil after water flooding in low-permeability reservoir，in view of Jidong oilfield reservoir condition with low permeability，severe channeling and suitable condition for chemical flooding，the system which had greater emulsifying capacity and lower interfacial tension and the other system which had lower emulsifying capacity and higher interfacial tension were selected. Flooding experiments after water flooding with these systems were carried out in the cores with similar permeability. The results showed that two compound systems which met the need of Gao 63-10 block in Jidong oilfield were obtained as follows: 0.2% nonionic surfactant 6501+0.1% anionic surfactant XPS and 0.1% XPS+0.5% NaCl. The former system had great emulsifying capacity and its interfacial tension could reach 10^-2 mN/m. The latter system had worse emulsifying capacity and its interfacial tension could reach 10^-3 mN/m. The enhanced oil recovery of 0.1% XPS+0.5% NaCl system after water flooding was 2.73%，while that of 0.2% 6501+0.1% XPS system was 5.78%. In low-permeability reservoir，oil displacement effect of emulsifying carry and coalescence to remaining oil and residual oil was better than that of interfacial activity. The combination of emulsion and interfacial tension （10^-2 mN/m） could reduce the requirements of interfacial activity which provided experiment basis and technical idea for screening surfactant in surfactant flooding.