Copper chromite catalyst was prepared with -alumina as support and used for oxidation of carbon monoxide in the temperature range between 180 and 300℃. The catalyst was found very active for the reaction. The reaction rate increased almost linearly with the partial pressure of carbon monoxide whereas it tended to decrease slightly as the oxygen partial pressure increased. The effects of the reaction temperature, the carbon monoxide partial pressure and the oxygen partial pressure were investigated systematically. By analyzing the experimental results it was confirmed that the reaction followed the dual site mechanism of Langmuir-Hinshelwood type, and the corresponding reaction rate equation was determined.