Occult syringoma means a clinically inapparent tumor of the swea gland that are histologically similar but not identical with the common syringoma. They may occur in a variety of inflammatory skin lesions and cutaneous neoplaams as a reactive process. We report herein a case of diffuse alopecia areata associated with occult syringoma in the scalp of a 57-year-old man. Our patient developed progressive, fairly well circ amscribed patches of alopecia and diffuse hair loss over a 1 month period. Histopathological examinaiion revealed non-scaring alopecia and a proliferation of eccrine ductal structures in the upper dermis. These ductal structures resembled syringoma. Only minimal focal fibrosis was occasionally observed arcund the hair follicles. We believe that occult syringona is a reactive process and is secondary to active inflarnmation or dermal fibrosis. It has been most commonly observed in scarring alobiecias but plays no significant role in the etiology of hair loss. (Kor J Dermatol 1994; 32(l): 163-166)