Abstract: A series of molybdenum phosphide (MoP) catalysts for the hydrogenation of acetic acid to ethanol were successfully synthesized and identified by means of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Scanning electron microscope (SEM). The results reveal that MoP₂O₇ and MoO₂ exist on the catalyst surface together with MoP. MoP or the synergistic effects of MoP₂O₇ and MoO₂ species play roles in hydrogenation of acetic acid to ethanol. Phosphating temperature significantly affects the formation and dispersion of phosphide. A low phosphating temperature is not sufficient for the formation of MoP, but a high phosphating temperature leads to the agglomeration of MoP. The catalyst reduced at 650℃ has the highest hydrogenation activity and its P/Mo molar ratio is 1.0.