This paper deals with the review of different literature. The review focuses light on analysis of sensitization and corrosion by the different authors for controlling sensitization and corrosion in ferritic stainless steel by using different welding processes. Besides the problem of low ductility and poor toughness of ferritic stainless steel, welds due to the microstructures characteristics of the weld section as a result of weld heat input rate and heat transfer rate factor , susceptibility to intergranular corrosion caused by the depletion of the chromium content of the weld matrix particularly in the HAZ is a major concern limiting the full deployment of the material in certain engineering application regardless its attractive economics combined with moderate strength and excellent corrosion characteristics of AISI 409 M. Ferritic stainless steel during welding (TIG,MIG, and SMAW) have been investigated. Its sensitization and corrosion can be evaluated by chemical exposure of the weld cross section. Then the characteristics of sensitization and corrosion can be analyzed using scanned electron microscope. This review concluded that variation in heat input resulted in significant changes in the mechanical properties of the weld which results on the sensitization and corrosion.