A stretch bending numerical study on one complicated car sub-frame profile using nonlinear FEM software MSC.Marc is presented. Firstly, it’s difficult to determine the jaw trajectory in force-controlled stretch bending. In order to solve this problem, a loading method of boundary condition on the end of the jaw is proposed. Secondly, the effect of element type and fillet element size on the springback prediction accurary is investigated. Numerical results show that solid-shell element is better than shell element on these problems. While the fillet element size is decreasing, spingback precision is increasing. The effect of pre-force on springback is also investigated. The larger the pre-force is, the smaller of the springback. When pre-force achieves a certain value, its effect on springback is not obvious.