MgAl hydrotalcite was synthesized and used as support for Li impregnation. MgAlLi oxides were obtained from heat treatment of the Li/MgAl hydrotalcite. These materials were characterized and evaluated as catalysts for model transesterification reactions. MgAl showed negligible activity under mild reaction conditions (50 A degrees C and 0.5 h) whereas Li incorporation greatly increased the activity. The activities were correlated to their basicity determined by TPD of CO2. Reuse tests showed catalyst deactivation after the third cycle, probably due to lithium leaching. However, the contribution to a homogeneous reaction has been dismissed. MgAlLi revealed to be a promising catalysts for transesterification reaction and thus for biodiesel production.