In this work, the FTIR and FT-Raman spectra of α-santonin have been recorded and vibrational analysis of the compound were carried out from the observed data. The molecular parameters such as bond length, bond angle, frequencies and spectral intensities were estimated with the help of density functional theory (DFT/B3LYP) method. The calculated and experimental spectra were compared and the stability of the molecule has been studied by the natural bond orbital analysis. The electronic properties like HOMO-LUMO have also been analyzed. The nonlinear optical properties of the molecule have been analyzed by calculating the first hyperpolarisability and comparing with urea.