Detonation gun spray coating method (D-Spray) [1] is one of the effective method of thermal spray coating process. The surface of material or substrate will be enhanced by deposition of coating powders such as metal oxides and ceramics like aluminium oxides, tungsten carbide,nickel chromium etc by D-spray method that prevents the metal from corrosion and to increase the wear resistance. This coating process had wide applications in different engineering sectors such as aviation industry, marine industry, biomedical industry etc., In this Experimental study the Process parameter optimization of D-spray coating process which is one of the Thermal spray Coating process was done by Taguchi method, [3] in order to find the best processing conditions and to get higher quality of coating. [6] Microhardness was estimated for various combinations of parameters and the optimum process parameters were obtained. Best combination of process parameters has been predicted which results that the thickness of the coating has got a major effect. © (2014) Trans Tech Publications, Switzerland.