Based on the analysis of applying IDEF0 model and ExtendSim simulation tool to study weapons equipment system architecture, an indirect generation method of a weapons equipment system architecture simulation model is proposed. Building IDEF0 models, the simulation of architecture under the environment of ExtendSim is analyzed. And the IDEF0 models are transformed into ExtendSim simulation models. Then, the simulation of weapons equipment system architecture is realized. The practice proves that the method could improve the efficiency and level of the whole modeling and simulation process in some extent.