Abstract: In order to solve the cracking problem of the torsion beam supportof a pure electric vehicleduringthe road test, a finite element model forelectric body structure was established by using finite element software. The load under typical working condition was extractedas its load input through multi-body dynamic analysis. Based on the strength theory, the inertia release principle was used to analyze the strength of the support. The analysis results show that the strength of the support has large risk of cracking, and the dangerous position is similar to the cracking position during the road test. In order to improve the strength of the support structure, an optimization scheme was put forward for the dangerous position. By increasing the strength of the support and transferring the load of the support, the stress distribution of the support structure can be effectively improved. Tracking the road test, the feasibility of the scheme was verified. Through the application of CAE analysis technology in the product development process, the cause of the problem can be found effectively and optimized in target, and thus the development cyclecan be shortened and costscan be saved.