The objective of this study is to find out the optimum hot corrosion resistance and hardness for Inconel718 coated by simultaneous yttrium-doped aluminizing-siliconizingprocess. The hot corrosion parameters selected for the experiments are Na2SO4, NaCl, and V2O5. The optimization is carried out by choosing three input parameters at two levels. Multi objective optimization technique, TOPSIS optimization approach is used for maximizing the hot corrosion resistance (minimizing hot corrosion rate Kp),and hardness. ANOVA is performed to investigate the more influencing parameters on the multiple performance characteristics. It also helps to calculate percentage contribution of each parameter. Finally, accuracy of optimization was confirmed by conducting confirmations. Results indicate feasibility of TOPSIS analysis in continuous improvement in hot corrosion resistance.