With the purpose of reducing gas consumption, this paper studies the optimization of control parameters of series-parallel LNG-electricity hybrid bus with super capacitor electric auxiliary. A simulation model of reference vehicle was established based on ADVISOR software. Meanwhile a top model of hybrid power system was constructed, and the performance simulation tests of vehicle were conducted according to actual operation conditions of buses in Guangzhou. Furthermore, the simulation model was coupled with ISIGHT software to study the influence of power coupling control strategy parameters upon vehicle gas consumption. In specific, the design parameters include the up and low limit of SOC of the super-capacitor, the limited speed of vehicle in pure electric model, the shutoff torque coefficient of engine, charging coefficient. With using Latin hypercube method, the simulation experiments were carried out and the gas consumption value under different control parameters was obtained. Henceforth，the approximate model of the relationship between control parameters and gas consumption was built with the application of the quadratic response method. With the application of the multi-island genetic algorithm method, the optimized values of control parameters were calculated. The results of optimization are shown as: the up limited value of super-capacitor SOC is 0.7021, the low limited value of super-capacitor SOC is 0.3662， the limited speed of vehicle in pure electric model is 6.9656 m/s, the shutoff torque coefficient of engine is 0.2903, charging coefficient is 0.3994. With the optimization of control parameters, the gas consumption of the modeled vehicle is reduced by 21.05%.