Abstract: Currently, the torsional fatigue testing methods of driving motors are no longer able to accurately simulate road load. In order to accurately conduct torsional fatigue tests on electric vehicle drive motors, this article upgrades the existing electric vehicle drive motor torsional fatigue test loading system based on the frequency domain iterative self-learning control method. Based on the structural principle of the torsional fatigue test loading system, a system simulation model is established and simulated. The strengthened road load on the test site is collected, and the upgraded torsional fatigue test loading system is experimentally verified. The results indicate that the improved experimental system can accurately simulate road load and has important engineering application value.