The present invention relates to an agent for promoting the production of ceramide covalently bonded to a horny cell, which contains a sphingolipid as an active ingredient. The present invention provides: a production promoter which can promote the production of ceramide covalently bonded to a horny cell, and which can safely, simply and economically prevent, inhibit or improve the deterioration of a barrier function of skin a composition and a food or beverage.