The reaction mechanism of (CH3)3CO with CO has been theoretically investigated using density-functional theory (DFT) calculations at B3LYP/6-31G* level. In order to get more reliable energy values the single-point energy is evaluated at CCSD (T)/6-31++G** level. The results show that the reaction is multi-channel and the reaction of (CH3)3CO radical with CO mostly produces (CH3)3C + CO2. The reaction could play a role in eliminating air pollution.