The features of the liquid-phase hydrogenolysis of glycerol to 1,2-propylene glycol over Cu/Al(2)O(3)catalysts (Cu = 2-80 wt %) and individual copper particles have been studied. It has been shown that the main factor determining the activity of the catalysts is the specific surface area of copper. It has been found that the Cu/Al(2)O(3)catalyst containing 60 wt % Cu is the most efficient. A new reaction mechanism is proposed based on the obtained data.