With the sustained development of CAD technology in the field of mechanical design, the volume of three-dimensional (3D) CAD model data has been growing exponentially. To meet the challenge of rapidly increasing 3D model repositories in the mechanical industry and the demand for efficient retrieval, this paper proposes a 3D model retrieval algorithm based on audio fingerprints and contour views for STL format 3D models. The aim is to provide mechanical designers with an efficient and accurate method of retrieving the required parts from the vast model repository.