Ophthalmopathy is a serious complication of Graves-Basedow disease. It is a common and the most significant symptom of this illness and usually persists even when other symptoms associated with abnormal thyroid function disappear. Despite of well-known auto-immunologic patho-genesis of ophthalmopathy it is still hard to predict when this severe complication will occur. This condition is thought to be associated with diagnosis and treatment errors. We studied the patients suffering from Graves-Basedow disease with and without ophthalmopathy. We concluded that the risk factors for ophthalmopathy were: many non-treated episodes of hyperthyroidism, delayed diagnosis and initiation of therapy, no thyroxine supplementation, improper preparation to strumectomy.