In the face of complex design tasks, traditional hand-drawn sketches and 3D reconstruction methods often require a huge investment of time, labor, and financial resources. In order to overcome these challenges, a geometric topology-based viewpoint recognition and 3D wireframe model reconstruction method for automobiles was proposed. A model library containing a small number of 3D wireframe models of automobiles was established, which was expanded to 3528 models by multi-scale scaling of body height, width, wheelbase and other parameters. The key point labeling of the car body adopted an interactive system developed based on Matlab, which utilized the labeled key points to match with the projection point sets of different viewpoints in the 3D wireframe model library to identify the angles of the car. The reconstruction of the complex 3D wireframe model was accomplished by using the least squares method with constraints based on the topological relationships of the key points in the 3D model. The reconstruction of 3D wireframe model of arbitrary vehicle types could be realized by updating the model in the model library and the positions of key points. The experimental results showed that the reconstruction time was about 33~44 seconds, and the error of key points was controlled within 32 mm. The reconstruction time and reconstruction error of this method were significantly lower those of the traditional reconstruction method in different viewpoints, demonstrating higher reconstruction efficiency and accuracy.