We describe a patient with panhypopituitarism whose only clinical symptoms were related to Raynaud's phenomenon. Previously described patients with Raynaud's phenomenon due to hypothyroidism had Hashimoto's thyroiditis, an autoimmune disease associated with multisystem autoimmune disorders. The occurrence of Raynaud's phenomenon in hypothyroidism without thyroiditis and its prompt disappearance with thyroid replacement therapy demonstrate that decreased thyroid function per se is a cause of this vasospastic syndrome. Raynaud's phenomenon may be an early clue to the diagnosis of hypothyroidism.