In this research work welding simulation was carries out in the FEA software to predict Fatigue life cycle and tensile strength in the joining of similar and dissimilar materials. The numerical simulations show that the concentration of stress is maximum near to the joint and at the corner where the cross section has suddenly changed. In order to find out the most optimum setting of material initially three different materials S40C, STS 304 and STS 316L [1] has selected for analysis. Fatigue analysis is performed to predict or estimate the life of weld joint. The test specimen first modeled in the geometry workbench and meshed by proper node and element then it tested under the given boundary condition by applying the tensile loading on one end while other end is fixed. Current project work consists of nine different welds joint with different combination of similar and dissimilar material and analysed with same boundary condition. A comparative study on the basis of stress and life is performing for all the combination of similar and dissimilar material and corresponding curve has plotted. The final selection of material is done by applying the stress life approach in finite element workbench. The result of numerical simulation in form of amount of stress for a butt welded joint is validated by the experimental result of V M Bansode [3].