La/ZrO2 catalysts were prepared by co-precipitation method. The physical and chemical properties of the catalysts were characterized by N-2 adsorption-desorption method, X-ray diffraction and temperature programmed desorption. The selective conversions of ethanol to propylene over these synthesized La/ZrO2 catalysts were also investigated. The optimum propylene yield reached 42.3% over La(1)/ZrO2 catalyst. A coordination of redox and acid-base properties accounts for the remarkable improvement of reaction performance over La/ZrO2 catalysts. On the basis of calculation results, the introduction of oxygen vacancy or La results in significant charge transfer. The Lewis acid-base (Zr-O) pair sites become more active as a result of charge transfer over La/ZrO2 catalysts. Furthermore, the formation of O vacancies over La/ZrO2 (101) is easier than that over t-ZrO2(101). Therefore, La modification improves the performance of ZrO2 on conversion of ethanol to propylene. [GRAPHICS] .