Surfactant with higher mass concentration from 1 000 mg/L to 3 000 mg/L is always used in ASP or SP flooding for getting ultra-low interfacial tension. Using surfactant with higher concentration does not always enhance the oil recovery, although it increases the cost of production. Through six displacement experiments, the most appropriate systems for Nanyang oilfield are selected. Using low concentration surfactant can improve the recovery efficiency significantly .The alkali/surfactant/polymer system can improve oil recovery by 22.3%, better than that of surfactant/polymer system, alkali/polymer system and polymer system. Before the displacement experiments, the oil-water interfacial tension, viscosity and viscoelasticity of flooding systems are tested. The conclusions are as follows: first,low-concentration surfactant can lower the interfacial tension to below 10-2 mN/m; second, the surfactant and the alkali used in this experiment can both influence the viscosity and viscoelasticity of the polymer.