With XMQ6103GF2 urban bus as the research object, to improve harmony of engine, batteries and electromotor of Parallel Hybrid Electric Vehicle（PHEV） and to achieve economical fuel and low emission for vehicle, the method of parameters match is studied. Requiring minimizing power and performance index, a method to match and optimize the parameters is introduced. The design is composed primary calculation, optimization and simulation. Use MATLAB and ADVISOR to simulate and analysis. From the simulation results, the control strategy is proved to be more effective.