Toxic multinodular goiter is rare in hemodialysis patients. In addition, establishing the diagnosis of hyperthyroidism in the elderly patient with renal failure is difficult because abnormal thyroid function tests can erroneously be attributed to euthyroid sick syndrome. Treatment of hyperthyroidism in dialysis patients by radioiodine ablation involves careful calculation of 131I dose, determination of interval between 131I administration and its removal by hemodialysis, and minimization of radiation hazards during dialytic removal of 131I. We described the clinical presentation of an elderly dialysis patient with toxic multinodular goiter and discussed our diagnostic and therapeutic approaches. The patient's recovery after 131I ablation was complete and uneventful.