A new catalytic system for oxidation of alcohols with oxygen by N-hydroxyphthalimide (NHPI) combined with CuBr has been developed. The reaction results showed that this catalytic system can effectively catalyze the oxidation of alcohols to the corresponding carboxylic acids or ketones. We obtained 100% selectivity for acetophenone at 94.2% conversion of phenylethanol at 75 °C for 20 h. A mechanism of oxidation of alcohols catalyzed by NHPI/CuBr was proposed.