Thiosemicarbazone of m-Nitrobenzaldehyde is an interesting organic crystal. It has been grown by slow evaporation solution growth technique (SESGT) using wood alcohol as solvent. The harvested crystals were purified by repeated recrystallization. The working groups of harvested crystals were examined by the Fourier Transform (FT-IR) spectral analysis. The UV-Visible Spectra are confirming the optical transparency. This is more helpful to use these crystals in electro optical applications. The harvested crystal Thiosemicarbazone of m-Nitrobenzaldehydewas characterized by proton nuclear magnetic resonance and of13C NMR spectra which show the molecular structure of the crystals. The TGA and DSC confirm the decay of the sample at 210oC. It further confirms the grown crystals Thiosemicarbazone of m-Nitrobenzaldehyde is thermally stable up to 210oC. The second harmonic generation efficiency of the powdered Thiosemicarbazone of m-Nitrobenzaldehydeand was tested using Nd: YAG laser and it is found to be 5.6 times higher than that of urea.