The present work is concerned with a thermodynamic study of 2,1,3-benzothiadiazole (general formula : C6H4N2S) It was achieved using three techniques : combustion calorimetry of small amounts of substance (a few milligrams); sublimation calorimetry, and differential thermal analysis. From this study, it was possible : to determine the enthalpies of combustion, sublimation and fusion of this compound as well as its triple point temperature.- to propose, from its theoretical resonance energy, a value for the energetical contribution of the S-N bond in Klages' scheme;- to propose, from its atomisation enthalpy, a value for H (S-N);- to determine, from its sublimation enthalpy, the energetical value of London forces and dipoles interactions.