Single crystals of salicylato complex of zinc with high degree of transparency were grown from aqueous solution by slow evaporation technique. The stoichiometric composition of the crystals is established by CHN analysis. Single crystal X- ray diffraction analysis reveals that the crystal belongs to monoclinic system with space group C 2. The FTIR spectra of the grown crystals were recorded and analyzed. The thermo gravimetric (TG) and differential thermal analyses (DTA) were carried out to understand the thermal stability of the sample. The kinetic and thermodynamic parameters were also calculated. The compound showed nonlinear optical property with Kurtz powder second harmonic generation test. Optical behaviour of the crystal was investigated using UV -Vis spectroscopy. The optical absorption study reveals the transparency of the crystal in the entire visible region. The optical band gap is found to be 4eV. The dielectric constants of the sample were also studied.