This work presents the characterization of 5-[(3,5-dimethylphenoxy)methyl]-1,3-oxazolidin-2-one (metaxalone) by DFT calculations and spectral techniques. The spectral analysis was carried out by using FT-IR and FT-Raman and 13C and 1H nuclear magnetic resonance (NMR) techniques. The FT-IR and FT-Raman spectrum were recorded in the range of 4000 to 400cm-1 and 4000 to 50cm-1 respectively. The over estimations of the calculated harmonic wavenumbers were efficiently corrected by the aid of a specific scaling procedure. 13C and 1H NMR chemical shifts of the molecule were calculated using gauge independent atomic orbital method (GIAO) and were compared with the experimental results. The molecular structure, fundamental vibrational frequencies and electronic structure calculations are carried out by density functional theory (DFT) method and B3LYP/ 6-311++G(d,p) basis set. Frontier molecular orbital energies, global reactivity descriptors and molecular electrostatic potential (MEP) were estimated. The thermodynamic properties at different temperatures were calculated revealing the correlations between standard heat capacities, entropy and enthalpy changes with temperatures.