Abstract: As a classic case of unfolding the complicated CAD models, this paper presents a rapid optimal algorithm using one-step inverse forming to simulate the process of stamping autobody panels on triangular meshes. Firstly an auxiliary mesh is produced after performing some pre-processing operations, such as hole-filling and local remeshing. An initial guess algorithm based on energy model is then applied to flatten the auxiliary mesh into a planar mesh accounting for shape distortion. The optimization process is conducted to refine the result further based on rapid large elasto-plastic deformation theory, which generates not only a good prediction of the blank shape for manufacturing but also a mesh parameterization with less area distortion and angular distortion. Numerical examples show the effectiveness of our new algorithm.