Cushing's disease is described in a child with a suprasellar germinoma. The patient presented with all of the classic stigmata of Cushing's disease as well as diabetes insipidus, but after surgical resection of the lesion was found to have pathology incompatible with an ACTH-secreting tumor. We believe that this is the first reported incidence of Cushing's disease associated with a suprasellar germinoma. The implications of this unusual association are discussed.