There are some problems in the development of heavy oil reservoir in Shengli oilfield，such as high viscosity and poor fluidity of crude oil，leading to unsatisfactory water drive recovery. To address this issue，an emulsification-stripping dual effect system consisting of betaine-based surfactant（CBT）and anionic/non-ionic surfactant（ASC）was constructed using emulsification instability coefficient，oil film shrinkage rate，and minimum emulsification speed as indicators. The emulsification and stripping ability of the dual-effect system for heavy oil was evaluated by indoor sand filling flow experiments，and then its mechanism was studied by using microscopic model. The results showed that CBT had excellent emulsification performance and significantly reduced the oil-water interfacial tension for heavy oil，while ASC had well stripping ability for heavy oil. The composite system had excellent emulsification and stripping properties. The dual-effect system increased the washing efficiency and changed the flow direction by emulsifying residual oil. At the same time，the wetting and osmosis of the system promoted the shrinkage and stripping of oil film on the solid wall. Under the condition of CBT/ASC composite system with a mass ratio of 3∶2 and the dosage of 0.3%， the recovery rate reached 50.36%，which increased by 14.18 percentage points comparing with water flooding. It had important guiding significance for the efficient development of heavy oil reservoir.