A process for preparing 1,3-propanediol comprising the steps of: (a) preparing an aqueous mixture of 3-hydroxypropanal, (b) passing said aqueous 3-hydroxypropanal mixture to a hydrogenation zone wherein the hydrogenation zone is comprised of at least two stages wherein the hydrogenation in the first stage is carried out under hydrogenation conditions at a temperature in the range of about 50 to about 130° C. in the presence of a fixed bed or slurry hydrogenation catalyst and wherein an acidic co-catalyst is added or present in at least one of the later stages and the hydrogenation in said later stages is carried out under hydrogenation conditions at a higher temperature than that of the first hydrogenation stage and in the range of about 70 to about 155° C. to form an aqueous solution of 1,3-propanediol; and (c) recovering said 1,3-propanediol.