Abstract: This paper deals with thermo-decomposition kinetics of thermo-decomposition and the influence of temperature on the products of thermo-de-composition of Hexapolyvanadate by differential thermal analysis, x-rays diffraction analysis,electronic diffraction analysis and chemical analysis. It indicated that the thermo-decomposition of Hexapolyvanadate in air is zero-order. Apparent activation energy equals to 53.618 KJ·mol^-1. The thermo-decomposition indicated that Hexapolyvanadate has one endo-thermal peak and one exothermal peak at 370℃ and 415℃ in air respectively. There is only one endothermal peak at 360℃ in nitrogen. Its decomposition is endothermal reaction. It produced V₃O₇ intermediate compound. Oxidation of V₃O₇ to V₂O₅ is endothermal reaction. When Hexapolyvanadate decomposed in inert gas, the temperature rose and the content of low valence Vanadium in the products incressed.