Cement is an important material in the construction of bridges, roads, dams, houses, etc. Cement industry accounting for about 8 to 10 percent of global anthropogenic CO2 emissions, consumes about 7% of the world’s industrial energy consumption and nonrenewable natural resources. Reusing wastes are one option to overcome aforementioned problems. The objective of this study was to investigate suitability of using waste ceramic powder enhanced water hyacinth ash as alternative cement replacement to see its effect on mortar property. The research method used was laboratory experimental study by preparing WHA and WCP mortar mix of OPC by 0-20% weightage of WCP and 0-15% weightage of WHA in binary blend and 0-30% in ternary blend. The samples were tested for soundness, consistency, setting time and workability as fresh property and at 3rd, 7th, 28th and 56th day to determine the compressive strengths, UPV, water absorption and sulfate attack of mortar based on ASTM procedures, and also thermo gravimetric analysis (TGA), Differential thermal analysis (DTA), and Fourier transform infrared (FT- IR) tests were conducted. Validity of the results were examined according to ASTM standards. RSM with CCD in Design-Expert offers a powerful, efficient approach to optimize mortar properties by reducing the number of trials and enabling detailed exploration of variable interactions. And unique by its accurate prediction of optimal condition, flexibility and adjustability of multiple responses. Workability of the Mortar mixes increase with the increase in the percentage of WHA However, WCP and ternary mix decreases the workability. Increasing WHA-WCP level up to 20% increased compressive strength and UPV. 20%WHA-WCP increased compressive strength by 17.99% at 28 days and 30.68% at 56 days. Mortar mixes containing WCP produces lower absorption compared to control, WHA and ternary mixes. The higher strength loss was observed in control mortar and followed by WHA blended mortar. Therefore, using WHA and WCP for mortar production gives better result up to 20% replacement. The Design-Expert software was used to design experiments. The R2 values of 0.9167, 0.8772, 0.9025, and 0.8816 for the compressive strength, UPV, water absorption and strength loss due to sulfate attack models, respectively, implied that all of the experimental data were fitted. The optimum properties achieved 6.95% WHA, 14.15% WCP as a cement replacement. Key words: Water hyacinth ash, waste ceramic powder, mechanical property, microstructure and RSM