Abstract: In order to obtain the spectra data and thermodynamic properties at different temperatures of N-benzylidene-4-[(2-cyanoimino-1, 3-thiazolidine-3-yl)methyl-thiazole-2-amine (C15H13N2S2) bioactive molecules, geometry structure optimization and frequency calculation were made using the B3LYP method of the density functional theory, and the electronic absorption spectra in gas and different solvent were calculated using the DT-B3LYP method of the time-dependent density functional theory. The results show that the most stable optimized structure is in good agreement with the experimental crystal structure. The peak of absorption is located at 370 nm in gas, near ultraviolet band, and solvents have no effect on the transition property, but increase the absorption intensity obviously. Moreover, there is a linear positive correlation between standard molar entropy and temperature, and the correlation coefficient is 0.999 05.