Based on acquiring the steady-state and dynamic data of grid,the simulation veracity in the case of uncertain load model parameters is analyzed in this paper,and in return the uncertain parameters are corrected using dynamic data of post-fault system. The genetic algorithm made some improvements is selected as correction algorithm. The load ratio is selected as inaccurate parameter in IEEE-39 system simulation,which can be extended to all model parameters of power system in actual application. Finally,the evaluation and improvement areas of this scheme are given.