This paper studied the characteristics of wet air oxidation (WAO) on polyether as non-ionic surfactant and analyzed its main intermediates. The results showed that, WAO was an effective method to treat non-ionic surfactants like polyether; temperature played a decisive role throughout the process: the COD removal percentage within 2 h was only 33.5% at 160 C, 57.2% at 200 C, and 94.4% at 240; fatty acid was the major intermediate, and oxidation of acetic acid was the key rate-determining step during fatty acid oxidation, and the oxidation of fatty acid could be accelerated by rising the temperature as well as elongating the reaction time. Meanwhile, oxidative decomposition of polyether and oxidation on fatty acid were the rate-determining steps to the whole WAO process, the oxidation of polyether was relatively more limited at lower temperature; on the contrary, the oxidation of fatty acid and other organics was obviously more limited at higher temperature. (c) 2010 Elsevier B.V. All rights reserved.