Abstract: A microreactor-GC apparatus has been used for studying COS hydrolysis reaction kinetics over TGH catalyst. The intrinsic reaction kinetics of COS hydrolysis over a TGH catalyst was investigated in the temperature range of 50 ℃～7 ℃, H2O/COS molar ratio of 60～550 with the presence of CO2. Nonlinear Marquart Regression was employed to analyze the experimental data. The reaction kinetics are expressed as follows: The kinetic model can be interpreted the reaction in terms of mechanism. The presence of CO2 seems not to change rate constant and activation energy of COS hydrolysis reaction.