Abstract: A kind of silicic acid gel was developed as a profile control system to increase oil production and control water production in Bohai offshore oilfields.The experiments indicated that the plugging efficiency of the gel system could be above 89%.The retention rate of plugging efficiency was 99.24% and 4.13% respectively corresponding to water measuring permeability of 7.95 μm² and 0.152 μm² when 23 PV and 22 PV water was injected respectively.Easily get ting into high permeability formation and large pores, increasing with the increase of permeability.In the parallel sand packs, the gel system could preferentially enter high-permeability layer and form effective plugging, which thus improved vertical profile and enhanced oil recovery in the high and low-permeability pack by 4.92% and 6.45% respectively. Considering its low cost and low pollution, the gel system performed great application prospect in offshore oilfields.