Abstract： A case of autoimmune polyglandular syndrome-3C is reported.A 68-year-old male presented with a half-year history of pretibial myxedema and a 19-year history of vitiligo.Ten months prior to the presentation,the patient developed symptoms and signs of hyperthyroidism with the increase of multiple antithyroid autoantibody levels.After two sessions of treatment with radioiodine (131I),the symptoms and signs of hyperthyroidism markedly improved.On admission,the patient presented with indifferent expression,exophthalmos,bilateral pretibial swelling which gave an orange peel-like appearance,and many hypopigmented patches on the trunk and extremities.Autoimmunity exerts essential role in the pathogenesis of vitiligo which is often accompanied by many other autoimmune diseases.More attention should be given to this phenomenon in clinic.