Clear cell hidradenoma was diagnosed in a girl at 3½ years of age. Only one case of hidradenoma has been documented in the first decade of life, although it remains unclear whether it was clear cell hidradenoma. This case demonstrates that clear cell hidradenoma is a rare differential diagnosis of cutaneous tumors even in young children, which is of special interest, because malignant transformations can occur. (J Am Acad Dermatol 2000;42:693-5.)