Abstract: During the simulation of a class of hybrid systems which consist of continuous systems, discrete event systems and inference decision systems, because the simulation of inference decision systems depends on other two systems, there are only different private simulation clocks between continuous systems and discrete event systems. This paper studies their simulation clock synchronization problem, and the equal step length synchronization method which bases on the equal step length of continuous system simulation, and the software realization method is given. Finally, the performance valuation method is also given, which can provide theoretical basis for the simulation of this class of hybrid systems.