The present invention provides a peptide and a composition which are suitable for oral ingestion, and which have a skin aging-inhibiting activity, a collagen-production promoting activity, an epidermal turnover promoting activity, and a cutaneous cell-proliferating effect. The present invention also provides a medicament and a functional food which have a skin aging-inhibiting activity, a collagen-production promoting activity, and a cutaneous cell-proliferation promoting activity. The present invention provides a composition including at least one peptide of Asn-lle-Pro-Pro-Leu, lle-Pro-Pro-Leu, lle-Pro-Pro, Pro-Val-Val-Val-Pro-Pro, Val-Pro-Pro-Phe, Val-Pro-Pro, Phe-Pro-Pro-Gln, and Leu-Pro-Pro-Thr.