The studies concerned with the oxidation of carbon monoxide on the nickel surface are reviewed. The Eley-Rideal (ER) collision and Langmuir-Hinshelwood (LH) adsorption mechanisms of the oxidation are analyzed. Calculations of the activation barriers of the oxidation of carbon monoxide on the Ni (111), (100), and (110) faces were performed for the first time and involved optimization of the reaction paths by the collision and adsorption mechanisms. It is shown that on the Ni (111) and (110) faces the ER collision mechanism of the reaction is preferable with the activation barriers ΔE dis O 2=62 kJ/mole and ΔE trans O A21F50012x=25 kJ/mole for Ni (111) and ΔE dis O 2=72 kJ/mole and ΔE trans O 2=20 kJ/mole for Ni (110); on the Ni (100) face, the LH adsorption mechanism with the activation barriers ΔE dis O 2=75 kJ/mole and ΔE trans O 2=42 kJ/mole is favored. Analysis of the potential barriers for the catalytic oxidation of carbon monoxide on the Ni surfaces suggests the LH mechanism to be preferential, although insignificant differences in the activation barries can lead to the oscillatory reaction mechanism, which is confirmed experimentally. The calculations were performed by the LCAO MO SCF method in the MINDO/3 approximation.