Through analyzing the tube-side thickening press hydraulic system, it is found that the root cause of the strong vibration of hydraulic system when pressure reliefing is the big volume of hydraulic cylinder relief chamber with more storing energy. Through adjusting the actual trip of hydraulic cylinder in different segments of the total trip，the volume of relief chamber was decreased，the energy saved in relief chamber was reduced. The energy released by the clamping cylinder pressure relief was reduced to 1/3，the energy released by the squeezing cylinder pressure relief was reduced to 1/2，which solve the problem of strong vibration in the system.