Abstract: In this paper a new method for optimizing and evaluating the network of warship combat system was suggested. Models of naval vessel combat system data net, and information flow of application layer,interface and behavior for each node were built up by OPNET＇s series cross-domain communication simulation software Modeler, the cross-domain communication for the whole combat system data net was realized. Network performances such as delay, flow and the utilization ratio of link circuits were obtained by simulation of the information flows for the combat system data net, thus the variation of network complexity with combat progress and the reliability of network were verified.