We report a 19-year-old male patient who had suffered from hairy nevocellular nevus on the left mandibular area since birth. He extracted hair from the nevus frequently. Histologic findings showed compound nevus with foreign body granuloma containing part of a hair in the dermis. Foreign body granuloma is more frequently associated with nevi on the face, supporting the hypothesis that it is caused by trauma. Patients who repeatedly fiddle with or pluck the hairs projecting from their facial nevi might be discouraged from doing so by the thought that this might lead to granuloma formation in their facial skin. (Korean J Dermatol 2000;38(11): 1547~1549)