SrO/MgO catalysts for biodiesel production were synthesized by the co-precipitation method. The formation of basic sites on the catalysts was investigated by SEM and XRD methods. The calcination temperature and SrO/MgO molar ratio affect the structure as well as the catalytic activities. Among the catalysts tested, the highest activity was found for a SrO/MgO molar ratio of 3:7 and calcination temperature of 850 ºC. The catalytic activities under transesterification reaction were also evaluated. The reaction conversion percentage of 80.45% was achieved within 2 h from the transesterification of n-butyl acetate with methanol with ratio of 5:1 at 95 ºC using 0.01 g the synthesized catalysts. The effects of calcinations temperature and molar ratio of methanol to butyl acetate were also investigated