A glycolic acid ester is produced by hydrogenating an oxalic acid diester of the formula, (COOR).sub.2, wherein R is a C.sub.1-6 alkyl group, with hydrogen in the presence of a solid catalyst comprising, for example, copper and silver metals carried on a solid carrier, and in the additional presence of an aliphatic alcohol, and collecting the resultant glycolic acid ester from the reaction mixture by distillation, preferably in the presence of an ester of a C.sub.3-12 dicarboxylic acid.