For the cracking problem of deepdrawn Ushaped longitudinal arm of SPCEN steel for a new energy vehicle，the finite element model was established，and the forming simulation calculation was conducted based on elastoplastic finite element theory. Then, the influences of upper die force and friction coefficient on the thinning rate of dangerous locations in forming results were analyzed. The results show that when the upper die force and friction coefficient change between 40-60 kN and 0.05-0.1, respectively, the thinning rate of dangerous locations increases first and then decreases. When the upper die force is 50 kN and the friction coefficient is 0.08, the thinning rate of dangerous locations is the smallest. The verified experiments show that when upper die force is 50 kN and the sheet material is oiled before forming to improve the friction condition, the cracking problem is effectively solved, and the yield of products with thickness of dangerous locations more than 1.45 mm increases from less than 60% to above 95%.