Leaf spring is widely used in automobiles and also one of the components of suspension system. It needs to have excellent fatigue life and less weight. As a general rule, the leaf spring must be regarded as a safety component as failure could lead to severe accidents. An attempt is made in this paper to study improve fatigue life of single composite spring with geometry optimization. The modeling of the original and optimized leaf spring is created using SOLIDWORK Software and was imported to ANSYS software for analysis. Finite element analysis (FEA) is performed to obtain maximum stress point or dangerous area, and life of original and optimized leaf spring using the ANSYS software with applying the boundary conditions. The maximum stress appears at eye end segment of the leaf spring. The FE model of the leaf spring geometry is meshed with tetrahedral elements. Mesh refinement are done on the leaf spring, so that fine mesh is obtained on the eye ends of spring, which are generally critical locations on leaf spring. The failure in the leaf spring initiated at the eye end segment of the spring, and fatigue is the dominant mechanism of failure. Geometry optimization resulted in 57% stress reduction and life is optimized by 89% of composite leaf spring, which was achieved by material changing. And weight of Eglass/Epoxy composite leaf spring is reduced by 84.4%. Then the results of Von-Mises stress, shear stress, weight, and life of leaf spring is done using ANSYS software results. From result of geometry optimization parameter like material changing and design optimization are changes in model of leaf spring improvement in fatigue life.