Abstract: For multi-assembly connections during 3D model assembly, a 3D assembly model retrieval method for multi-assembly interfaces is proposed. First, the 3D assembly models are expressed using an attribute adjacency graph, and a conjugated subgraph is defined based on the interface cooperation relationship between the assembly parts. Second, serialization of the vertices of the graph is performed for the atlas of the assembly model, reducing the times of traversal during the process of vertex matching. On this basis, the assembly model retrieval is translated into the problem of retrieving the attributed adjacency graph that conforms to a conjugated subgraph, and model retrieval is performed through the atlas of the attribute adjacency graph of the assembly model. Finally, the frequent subgraph mining method is improved, and the 3D assembly model that satisfies the multi-assembly interface is extracted. Experimental results show that this method can realize the 3D assembly model retrieval of multi-assembly interfaces, extract the 3D model required by designers, and improve product design efficiency.