Keratoacanthoma is a cutaneous tumor that most often presents as a solitary lesion in middle-aged to elderly, light-skinned individuals on sun-exposed areas. It is characterized by rapid growth and may be followed by spontaneous involution. This is a case of a seventy-year-old Filipino male who had a one month history of a solitary nodule that suddenly appeared on an epidermal nevus. Histopathologic diagnosis revealed a keratoacanthoma.