In the present study, single crystals of potassium dihydrogen orthophosphate and chrysoidine y doped potassium dihydrogen orthophosphate are grown by slow solvent evaporation method. The incorporation of chrysoidine y in potassium dihydrogen orthophosphate crystal lattice is confirmed from the powder xrd and energy dispersive x-ray analysis. A strong absorbance peak is present in the uv-visible transmittance spectrum confirming the chrysoidine y doping in potassium dihydrogen orthophosphate crystal. The optical bandgap energy of the doped crystal is 3.65 eV and they possess lower urbach energy. The mechanical properties confirmed that the grown crystal is a soft material having reverse indentation size effect and the doped crystal has enhanced hardness properties. The chrysoidine y doped potassium dihydrogen orthophosphate crystal has lower ac activation energy and are more thermally stable.