Abstract: A new solid base，CaO-ZrO2 nanocomposite，was prepared via an appropriate sol-gel process. It was found that such nanostructure greatly improved the basic strength and durability of the solid base catalyst. Temperature programmed desorption of CO2 (CO2-TPD) and X-ray photoelectron spectroscopy (XPS) demonstrated that both weak and strong basic sites coexisted on the surface of CaO-ZrO2 nanocomposite. At the same time，the mesoporous CaO-ZrO2 nanocomposite showed high thermal stability，since X-ray diffraction (XRD)，transmission electron microscopy (TEM) proved that the mesoporous network of this material was preserved well even up to 700ºC. As a result，this novel solid base showed remarkable activity and stability in the synthesis of dimethyl carbonate (DMC) from propylene carbonate and methanol.