Abstract: The oxidation kinetics of the cotton fibers with TEMPO was investigated. The results showed that the oxidation reaction of the cotton fibers by TEMPO/NaClO/NaBr system could be approximately described in two pseudofirstorder reaction kinetics based on the special cellulose structure，namely the dynamics of amorphous and crystall regions. In the concentration range used, the rate constant k was directly proportional to the concentration of TEMPO. As to NaBr，the rate constant was proportional to the concentration in a relatively lower range，but oxidation reaction rate did not increase with concentration of NaBr when its concentration was above 10 mmol/g. The effect of temperature on the rate constant could be well described by Arrhenius equation，the apparent activation energy measured was about 5666 kJ/mol.