In view of the increasing demand for unmanned systems in future wars, a new type of unmanned system suitable for narrow space and complex environment, amphibious unmanned combat vehicle system is proposed, which has the capabilities of ground driving, wall crawling, air flight and cooperative combat. The Agent-based modeling and simulation (ABMS) method is used to analyze the functions of the amphibious unmanned combat vehicle system by constructing the task scenario, desktop model and simulation verification based on the analysis of its application task scenario. According to the analysis results, the key technologies needed to be solved are put forward. The results show that the system is of great significance to expand the unmanned system mission environment and enhance the autonomous combat capability.