The component rocker arm is one of the most important parts in valve actuating mechanism of an internal combustion engine. From many years research is going on in the automotive industries considering various factors of optimization like cost, weight, stresses, material compositions, etc. The failure of the rocker arm in valve actuating mechanism is measure concern. To study and analyze stresses generated, we are modelling rocker arm using CATIA CAD software and the various regions of stresses and deformations found out using OPTISTRUCT-RADIOSS structural analysis solver which gives solution for structural optimization using finite element analysis (FEA). In this project, we are using four different materials preferred in industries which are structural steel, aluminium, carbon steel and HMCF (High modulus carbon fibre). So by comparing analytical results and FEA results for all above materials we can study stress level and deformation in rocker arm at extreme load conditions and going to propose best suitable material among above materials on the basis of strength, durability, life and cost of material. The main purpose of this study is to determine the value of stresses in rocker arm at extreme conditions.