Abstract: Weak gel-surface acting agent profiling can greatly enhance oil recovery,based on the evaluation of weak gel viscosity,surface acting agent and boundary tension of crude oil,optimized high efficiency weak gel-surface acting agent system,the formulas of this system are composed of 2000 mg/L AP-P3+,5 to 40 mg/L Cr3+,500 mg/L SDBS surface acting agent,the gel of this system can keep steady for more than half one year at 60℃.boundary tension little than 10-2 mN/m,and the weak gel matched well with surface acting agent.The physical model displacement experiment showed:no oil produce after water flooding,use 0.4 PV weak gel flooding,then use 0.4 PV surface acting agent,and then use 0.4 PV 1800 mg/L polymer solution to form a protect plunger,this will enhanced 19.6% recovery ratio of heterosphere and 31.4% of low permeability layer.