Background: Recently, a great deal of attention has been directed toward the use of crude extracts from natural products for cosmetic applications. Thus, we performed a series of experiments to investigate skin depigmenting properties of a crude extract that was derived from a traditional Korean medicinal plant. Materials and Methods: In this study, the depigmentational potency of Cyrtomium fortunei J. Smith was investigated. The inhibitory effects of the root of Cyrtomium fortunei J. Smith extract on melanin production were evaluated by assessing its tyrosinase inhibitory effects, melanin production-inhibitory properties in melan-a cells and depigmenting ability in brown guinea pig skin. Results: The methanolic extract of the root of Cyrtomium fortunei J. Smith appeared to inhibit tyrosinase activity and melanin production in melan-a cells. In addition, this extract exhibited depigmenting ability on Ultra violet-induced hyper pigmentation in brown guinea pig skin. Conclusion: These results suggested that root of Cyrtomium fortunei J. Smith might prove useful in treating skin hyperpigmentation associated with excess sun-exposure.