In this paper, the effect of catalyst preparation on the activity of supported Cu catalyst for oxidative carbonylation of methanol to dimethyl carbonate was investigated. The results showed that after addING metal hydroxide, the supported Cu catalyst enhanced the conversion of methanol and the selectivity TO of DMC and the suitable mole ratio of OH/Cu is 1.0. The optimum Cu content lies in 6 10wt.% and varies with reaction temperature. The suitable calcination temperature range is 200～300℃ considering both factors of methanol conversion and DMC selectivity. The effect of particle size of the catalysts on the activity is negligible.