The present work is a comparative analysis of the properties of undoped and L-Proline doped ADP crystals. Slow evaporation solution growth technique was employed for growing undoped and L-Proline doped ADP crystals. The unit cell parameters were estimated by single crystal X-Ray diffraction analysis. The crystalline nature of the samples was revealed by Powder X-Ray diffraction analysis. The presence of functional groups and the spectral properties was identified by FTIR spectral analysis. The optical property of the material was examined by UV-Visible spectral analysis. The surface morphology and the elemental composition of the material was studied by SEM and EDS analysis.  The nonlinear optical property of the samples was tested by Kurtz and Perry experimental setup.