The thesis manly focused on the optimization of leaf spring lead to reduce stress. A leaf spring is a simple form of spring, generally used for the suspension system. Mostly the comfortably and life span of the parts of a vehicle is not compatible. To solve this problem the automobile industries are trying to make new vehicle which can provide high efficiency with low cost. The automobile vehicles have different parts, which can be replaced by composite material, through which the weight can also be reduced. It has more elastic strength and high strength with weight ratio has compared with those of steel material. So, among those many components in automobile, the leaf spring is used for providing the cushion effect for the vehicle in order to increase damping force, which transits from the variations in the road to the vehicle load. To reduce stress occurring in the existing steel leaf spring, it has been modified with fibre material and coated with molybdenum, so that the generating stress can be reduced. To execute this idea, four different polymer composite materials and one coating have been selected. The selected materials for modified leaves in the leaf spring are E-glass/epoxy, Carbon epoxy, Graphite epoxy and Bamboo polyester composite material, which are more economical and effective damping system of load transfer. The analysis was carried out in simulation software ANSYS 15.1 with same loading condition for deflection and bending stress of steel as well as E-glass/epoxy, Carbon epoxy, Graphite epoxy and Bamboo composite materials. From the analysis, the maximum displacement of complete steel leaf spring is 1.2144 mm and the corresponding displacements in composite leaf springs Eglass/epoxy, Carbon epoxy, Graphite epoxy and Bamboo polyester after coating with molybdenum are 1.517 mm, 1.5469 mm, 1.5395 mm, and 1.5726 mm respectively. Also, the von-mises stress in the complete steel leaf spring is found to be 508.33 MPa, where as in E-glass/epoxy, Carbon epoxy, Graphite epoxy and Bamboo polyester composite leaf springs without coating, it is 518.29, 553.65, 547.19 and 555.23 MPa respectively. After coating with molybdenum in the composite leaf springs, the stress reduces to 406.6, 463.5, 423.73 and 459.16 MPa respectively. All four composite leaf springs have good strength to weight ratio, than that of existing steel leaf spring.