Trichilemmal horn (trichilemmal keratosis) is a rare keratinizing tumor that resembles a cutaneous horn. Histologically,it is characterized by an abrupt maturation of keratinocytes into lamellar keratin without the formation of a granular layer. We describe a case of a trichilemmal horn on the right cheek of a 78-year-old woman. (Ann Dermatol 13(2) 110~112, 2001).