The main hydraulic jacking system was designed for earth pressure balance pipe jacking machine aiming at its functional requirements. Its working condition was analyzed for calculating total jacking force and maximum hydraulic jacking force of the main hydraulic jacking system. The parameters of the hydraulic system were calculated according to the maximum hydraulic jacking force,and the synchronous circuit, direction control circuit and oil supply mode were designed by comparison. The pressure loss and working temperature of the main hydraulic jacking system were checked. The results show that the pressure loss and the working temperature of the hydraulic system are proper.