In order to solve the problems of information overload and knowledge search inefficiency in the information process of equipment maintenance support, this paper puts forward the application of knowledge graph to the construction of equipment maintenance support knowledge base. We mainly use the internal data sources of equipment maintenance support to extract key information, put forward the construction process of the knowledge graph of equipment maintenance support. Then we analyze the military application of the knowledge graph of the equipment maintenance support, and point out the application value of the knowledge graph in the field of equipment maintenance support. The results show that this method is helpful for maintenance support personnel to acquire knowledge quickly and accurately, enhance knowledge sharing and improve maintenance support capability under information condition.