The present invention has an object of revealing an epidermis regeneration effect of various chitin derivatives and providing an agent for therapy or treatment for wound which can be clinically used effectively.According to the present invention, it has been evidenced that N-acetyl-D-glucosamine has an effect of promoting proliferation of an epidermis keratinized cell. Accordingly, the present invention provides a proliferation promoting agent for epidermis keratinized cell comprising N-acetyl-D-glucosamine. According to another aspect of the present invention, there is provided a regeneration promoting agent or protecting agent for epithelium, skin or dermis comprising the proliferation promoting agent. Further, a therapeutic agent for wound is provided.
