Potassium dihydrogen phosphate is a material rich in NLO property with wide range of industrial applications. Certain Amino acids are also rich in NLO properties so they are used as dopants. In the present work Sacrosine one of the twenty amino acid is added in the ratio 1:1 molar percentage to KDP. Single crystals were grown by slow evaporation method. The grown crystals were characterized by powder X-ray diffraction, Single crystal X-Ray diffraction, UV–vis. -spectroscopy, Fourier transform infrared spectroscopy (FTIR), SHG efficiency, Dielectric and Micro hardness studies. The single crystal X-ray diffraction studies reveal the structure and space group of the crystal. The powder X-ray diffraction study shows that the crystalline perfection of grown crystal is good. Fourier transform infrared studies confirm the functional groups of the crystals. It is seen from UV–vis studies that the optical transparency is found to increase much by adding chlorides. SHG efficiency of KDP is found to be slightly increasing with doping of Sacrosine. Dielectric studies show the conductivity and electrical behaviour of the crystal. Micro hardness studies show the mechanical stability of the crystal.