The combination features like low cost and low weight with moderate quality are the present significant requirement. All these features are well satisfied by different Aluminium (Al) alloy combinations, so the utilizations of Al alloys are growing day-by-day. These alloys are promptly replaceable steels in numerousapplications since the resistance of corrosion characteristic is one more attractive feature apart from other characteristics like low weight and low cost. The welding of Al and its various alloy combinations with customary combination welding methods regularly delivers a weld with various defects, for example, slaginclusions, voids, porosity. Because of these imperfections, the quality of the weld joint reduces drastically. Friction Stir Welding (FSW) is a recently developed process for joining different materials. This process is developed and patented by TWI, The Welding Institute, UK. These process procedures take place below the melting point of the material to be welded. Solid-state nature of this procedure overcomes many welding imperfections which generally happen during the conventional type of fusion welding combinations. HenceforthFSW produces a sensibly high-quality weld joint with the non-appearance of melt related imperfections. Joining of a dissimilar Al alloy joints of AA6351 with AA5083 is broadly valuable in aviation and shipbuilding. Particularly it is extremely valuable in marine-related industries due to the characteristic of alloy AA5083 which is corrosion resistant in seawater. In this work, a trial of experiments has been done to improve the quality of the weld joint by adding Copper and Zinc materials in coating form to AA6351 and AA5083 alloys. These coated 5 mm thick dissimilar Al plates are friction stir (FS) welded by utilizing the Taguchi technique with three variables factors and three levels.