Depolymerization of thermosetting epoxy resin with environmental-friendly heteropolyacid catalyst at temperatures between 270°C-350°C in H2O medium. The effect of the factors catalyst, temperature and time on the depolymerization was researched. UV spectrum was used to characterize the thermal stability of heteropolyacid catalyst. The products of depolymerization were analysed qualitatively and quantitatively by means of GC/MS and GC. The results indicated that the main depolymerized products were phenol, p-isopropylphenol and bisphenol-A (BPA). The results showed adding heteropolyacid contribute to enhancing the rate of depolymerization and increasing the yield of BPA. Also, the depolymerization kinetics of epoxy resin was researched and the activation energy was calculated.