The pump/motor in traditional rearmounted parallel hydraulic hybrid vehicle will have longterm overspeed or lowspeed operating conditions during operation. In order to improve the fuel economy of vehicles and make the pump/motor working in the high efficiency range as much as possible, the torque coupler was put forward to be placed between the engine and the transmission, which was called the front-mounted parallel structure. Its feature was that the hydraulic hybrid system would increase the torque after adjusting the speed of the transmission, and then the power was transfered to the drive axle. By setting the simulation model of the hydraulic hybrid vehicle, the engine power, fuel consumption, starting acceleration performance of the vehicle were compared and analyzed, and the experimental vehicle verification was carried out. The results show that the front-mounted parallel structure has a high energy recovery and reuse rate, and the energy saving effect is obvious. Using this structure, the dynamic performance and climbing performance of the vehicle can be improved effectively.