According to the effect of profile control gradually become poor after multi-round profile control in offshore oilfield, a secondary crosslinking gel system was developed which gel time and strength were controllable. By changing the molar ratio of acetic acid to adipic acid, the gel time and gel strength can be control at different stages. Through enhancing the initial strength of the profile control system, expand sweep volume in the process of gel injection, and improve profile control effect after multi-round profile control. Performance of the secondary crosslinking gel system was evaluated in Bohai S Oilfield condition, and the formula was selected. Studies have shown that secondary crosslinking gel system has the best matching performance with highSpermeabilitySbelt when the system concentration is 3000mg/L polymer and 4000mg/L crosslinking agent, and molar ratio of acetic acid to adipic acid is 1:3. Displacement experiment with flat plate model show that water flooding recovery was enhanced 16.05% after injecting profile control system. The results are applied to the S oilfield which lead to a decrease of 8.4% in water cut and a increase of 18288 m3 of oil production.