Abstract: A comprehensive computer simulation has been developed to predict the performance of a direct-injection stratified-charge rotary combustion engine by means of the zero-dimensional thermodynamic cycle model. With giving the model,the chamber pressure and temperature are available during a complete engine cycle. By the chamber pressure,the overall engine performance parameters can be calculated. The model can be used as an analytical tool for the preliminary design and development of the direct-injection stratified-charge rotary combustion engine.