AbstractA simplified catalytic system K‐Cu/Al2O3 (KCA‐xCu‐T) with Cu‐Al oxides was prepared by a facile impregnation method and was successfully applied in the direct synthesis of ethanol from syngas. The results demonstrated that the distribution of CuO, CuAl2O4, and CuAlO2 in KCA‐xCu‐T catalysts can be effectively tuned by varying the calcination temperature (T/°C) and CuO loading (xCu/wt%). The cooperative effect between Cu0 and CuAlO2(Cu+) was proved to be responsible for the enhanced ethanol selectivity. Furthermore, the formation of CuAlO2 could efficiently fix Cu+ species in KCA‐10Cu‐900 sample, and thus lead to excellent catalytic stability (300 h at 400 °C). CuAl2O4 itself has no catalytic effect but can be gradually decomposed into Cu+ and/or Cu0 species during reaction, which further influenced the ethanol selectivity (38.4 wt%).