Aluminum profile is used in various fields such as aeronautics and automobile industries to get light products. As one of main forming process to obtain the profile part, stretch-wrap bending becomes the major development direction of advanced plastic forming technology, so prediction and control of forming defects have become a difficult and key problem urgently to be resolved in research and development of this forming process. However, this is an intricate process affected by many interactive multi-factor effects; it is difficult to get ideal solution for process design by using only theoretical analysis and experiment. Therefore numerical simulation based on FEM is used to analyze the forming mechanism, to predict the defects and to optimize the process parameters. The technology of plastic sheet metal forming and its theoretical analysis are globally introduced. On this foundation a study on stretch-wrap bending processes on hollow section profile is conducted to analyze stress and strain distribution under different loadings. The agreement between the experiments and the simulations is fairly good for most cases, which proves the validity of the established numerical model.