This study proposed to discuss a novel nonlinear optical material Ammonium Dihydrogen Orthophosphate (ADP) doped with L-Asparagine (LAADP) which was grown by slow evaporation technique from the mixture of aqueous solutions of L- Asparagine and ADP at an ambient temperature. Studies on structural, optical properties of the crystal were carried out. Formation of the new crystal has been confirmed by Powder XRD and FTIR spectra. LAADP belongs to orthorhombic system. Optical transmission spectra revealed the optical properties of the grown crystal. The thermal stability of the crystal was investigated using thermo-gravimetric analysis. Vicker’s Hardness number (Hv) increases with increase in load. The NLO property of the crystal was confirmed by powder SHG test.