In previous work,we observed that a large amount of H2O2 decomposed for direct adipic acid synthesis at high temperature and atmospheric pressure in micro-flow packed-bed reactors,which significantly affected the reaction process.1,2 In order to better understand the H2O2 decomposition process,the kinetic study of H2O2 decomposition catalysed by sodium tungstate at high temperature and high pressure(10 bar)was first done in PFA capillary and stainless steel capillary,respectively.The reaction is found to be zeroth order with respect to H2O2 and first order to sodium tungstate in PFA capillary.