In order to solve the problems of the lack of effective management and reusability of ship welding procedure knowledge,a method based on ontology for ship welding procedure knowledge graph is proposed. Firstly,based on the ship welding procedure content,the ship welding procedure knowledge is condensed,the welding procedure knowledge ontology is established,and the semantic relationship extraction between entities and concepts is completed based on the third-order tensor triplet method. Secondly,the welding procedure knowledge graph is constructed according to the acquired entity and its semantic relationship,and a graph mechanism between ontology and knowledge graph is established;Finally,in order to avoid the repeated storage of the common attributes of the concept,the welding procedure knowledge is stored by considering the hierarchical table structure model. On this basis,the ship welding procedure knowledge management system is designed and developed,and the knowledge graph is used to realize the expression and semantic retrieval of the welding process knowledge,and the rationality of the ship welding procedure knowledge graph construction method is verified.