We report a case of a 25-year-old woman with systematized epidermal nevi associated with alopecia universalis and onychodystrophy. The histopathologic examinations by light and electron microscopies of the epidermis of the trunk and scalp lesions showed epidermal nevus with characteristic features of epidermolytic hyperkeratosis. This is a rare case of systematized epidermal nevi associated with congenital alopecia universalis and onychodystrophy. Though there is no apparent gross skin lesion on the hair bearing area, the development of epidermal nevi can affect the hair and nail units which are derived from the common epidermal germinative cells.