Pure and Delonix leaf extract added ammonium dihydrogen phosphate (ADP) single crystals have been grown at room temperature by the slow evaporation method. The grown crystals have been characterized structurally, chemically, thermally, mechanically and optically using the available standard methods. The powder X-ray diffraction and Fourier Transform Infrared Spectral measurements confirm the crystal and molecular structures. Thermogravimetric, UV-Visible spectral and micro hardness measurements indicate respectively the thermal stability, optical transparency and mechanical stability of the grown crystals. Result of the scanning electron microscope indicating the morphology of the pure ADP and doped crystals via, spherical and coarse shape. From the single XRD the lattice parameter values are a= 7.53 Å, b= 7.53 Å, and c= 7.58 Å with angles α= β= γ= 90̊belongs to tetragonal structure.
