The invention provides a composition for promoting collagen production, and more specifically, provides a composition capable of promoting collagen production in human dermis. Further, the invention provides a method for promoting collagen production. The invention provides a composition for promoting collagen production containing a purine nucleic acid-related substance as an active ingredient as well as a composition for promoting collagen production containing a purine nucleic acid-related substance and a pyrimidine nucleic acid-related substance. The method for promoting collagen production of the invention comprises applying a purine nucleic acid-related substance alone or in combination with a pyrimidine nucleic acid-related substance to the skin.