MgO-La2O3 catalysts with different Mg/La molar ratio were synthesized by a precipitation method and a subsequent calcination and then characterized by x-ray diffraction, N2 adsorption-desorption isotherms (at −196 °C), CO2- and NH3-thermoprogrammed desorption and x-ray photoelectronic spectroscopy. The coexistence of acid and basic sites promoted the selective transformation of ethanol into valuable products. Thus, MgO catalyst promoted the Guerbet reaction obtaining n-butanol as product while the incorporation of La2O3 in the catalytic system improved the ethanol conversion notably, obtaining ethylene as the main product due to a dehydration reaction. The highest ethylene yield was obtained for the catalyst with a Mg/La molar ratio of 1. Display omitted •The coexistence of acid and basic sites promotes the selective transformation of ethanol.•MgO catalyst promotes the Guerbet reaction obtaining n-butanol as main product.•The presence of La2O3 in Mg-La-O catalysts improves the ethanol conversion to ethylene.•The highest ethylene yield was obtained for the catalyst with a Mg/La molar ratio of 1.