Abstract: A hydrogenation catalyst composition for use in the hydrogenation of a lower alkyl ester of a lower hydroxycarboxylic acid. The composition is composed of a reduction product of copper-containing silica gel formed by contacting an ammine complex of copper with silica gel having an average particle diameter of not more than 200 microns or colloidal silica sol. A process for producing the catalyst composition is also provided. By using the aforesaid catalyst composition, a lower alkylene glycol can be produced efficiently in high conversions and selectivities without causing pollution attributed to the use of a chromium-containing catalyst composition.