Abstract: Ru-La₂O₃/ Al₂O₃catalyst for the CO removal via selective catalytic oxidation was prepared by means of impregnation, and the corresponding intrinsic reaction kinetics was investigated. Experimental results show that the surface reaction on the catalyst bed plays the most important role in the control of reaction rate, and that, when eliminating the internal and external diffusion, the catalytic oxidation of CO on the catalyst bed is a first -order reaction with an activation energy of 76.24kJ/mol.