Pure silica mesoporous molecular sieves MCM-41 and MCM-48 organofunctionalized with 3-aminopropyltrimethoxysilane and N-[(3-trimethoxysilyl) propyl] ethylene-diamine, respectively, were served as supports to immobilize CuCl2 with conventional impregnation method. The supported copper catalysts showed a considerable enhancement in the reaction rate in heterogeneous vapor-phase oxidative carbonylation of methanol to produce dimethyl carbonate in comparison with that obtained by CuCl2-supported nonfunctionalized mesoporous silicas under identical conditions. The electronic donation of the amino groups, the accessibility and dischargeability of reactants in the regular mesopores probably account for the good catalytic performance as evidenced by the characteristic studies with XRD, BET, FTIR, TG- DTA, and XPS.