Abstract: In this paper, the leaf spring of a commercial vehicle is taken as the research object, and the traditional leaf spring is replaced by glass fiber composite materials to reduce the mass of vehicle suspension, the stiffness, strength and fatigue simulation analysis models of composite leaf spring and leaf spring were calibrated by simulation and test, and the consistency of simulation and test was ensured to verify the existence of simulation models. At the same time, through comparative analysis, the results show that the use of composite leaf springs not only achieves the purpose of lightweight, but also improves all aspects of the performance of leaf springs, which provides theoretical support for suspension structure optimization design and performance evaluation.