Abstract: Firstly, a simulation model of asynchronous generator based on Matlab/Simulink was built, and correlative parameters of the model of asynchronous generator were confirmed in M file in view of data of case asynchronous motor. Secondly, realization procedure and principle of modeling of four-stroke internal combustion in Matlab were explained in details. Finally, self-excited asynchronous generator system driven by internal combustion was established. The simulation results showed that the system has an obvious adjusting process when it is connected with load. The correctness of the model was verified through analysis of change of voltage with prime mover or not. It provided theoretical basis for developing actual self-excited asynchronous generator system driven by internal combustion.