Abstract: The EOR potentiality of ASP flooding after polymer flooding has been studied by reservoir numerical simulation. According to the pilot , the optimum injection proceeding of chemical material was 0.1PV polymer preslug , 0.45PV ASP main slug , 0.05PV polymer follow-up protective slug by the orthogonal experiment , and then three projects of well patterns were designed on the basis of the feature of pilot.The results demonstrate that the ASP flooding can further enhance oil recovery by 12.9%than the polymer flooding.In combination with horizontal wells and vertical wells , the project has the biggest potentiality and the EOR is 15. 97%.Therefore , the multiple advantages of horizontal wells adjustments and ASP flooding should be considered after polymer flooding so that the better development effect to be anticipated.