PROBLEM TO BE SOLVED: To provide a ceramide production promoter having ceramide production promoting effect, a humectant for enhancing or improving skin moisture-retaining capacity, an agent for enhancing or improving skin barrier capacity, and an agent for giving firmness or resilience to the hair or an agent for improving the texture of the hair.SOLUTION: This invention relates to a ceramide production promoter, a humectant, or a skin barrier capacity enhancing or improving agent comprising roburic acid or salt thereof as an active ingredient.