Abstract: In order to make better use of the reusable generic structure information of 3D assembly model,reduce the repetitive labor and shorten the product development cycle,a method for discovering common structure of 3D assembly model is proposed.Firstly,on the basis of the attributed adjacency graph of each part of the 3D assembly model,the information of assembly characteristic attribute is kept,and the information of non-assembly characteristic attribute is simplified to form the attributed assembly feature adjacency graph.Secondly,based on the assembly relationship among the parts of the 3D assembly model,the attributed assembly feature adjacency graphs of the parts to form a 3D assembly model attributed adjacency map.Thirdly,the common structure of 3D assembly model is extracted by frequent subgraph mining algorithm.Finally,a set of fixture models is taken as examples to verify the results.The results show that the method for discovering the common structure of 3D assembly model can accurately and effectively explore the common structural information in the product,and have a good application effect.