[en] HTLV-I carriers or patients with HTLV-I associated myelopathy (HAM) are prone to immune-mediated inflammatory disorders. We present a 44-year-old female with HAM who developed Graves' disease. She developed severe Graves' ophthalmopathy shortly after ¹³¹I therapy, concurrently with a remarkable increase in TSH-receptor antibody titer. Ophthalmopathy was aggravated in spite of prednisolone therapy and euthyroidism being maintained by thyroxine replacement. Uveitis also developed after ¹³¹I therapy and iridocyclitis finally required trabeculotomy. This case suggests that HAM patients may have a higher risk of immune-mediated Graves' ophthalmopathy after ¹³¹I therapy.(author)