A CaO/C composite, a new solid base catalyst, was prepared and served as a convenient and efficient heterogeneous catalyst for synthesis of DMC from methanol and propylene carbonate. Compared with pure CaO, the CaO/C shows the same basic properties and a high performance. In addition, the CaO/C catalyst, which is easily recovered, can be reused with little deactivation, if a suitable particle size is chosen.