Introduction: One of the most common causes of hyperthyroidism is Graves’ disease. The malignant exophthalmos is a rare condition characterized by the loss of visual function that doesn’t adequately respond to various forms of treatment, requiring, in most cases, surgical correction. Objective: We report a case of conjunctival edema and protrusion of the eyeball in patients secondary to Graves’ disease, characterizing malignant ophthalmopathy and discuss their surgical treatment. Case Report: A 73-year-old male patient presenting bilateral conjunctive hyperaemia, decreased visual acuity, exophtalmos with progressive deterioration. Pulse therapy was performed without improvement and then underwent bilateral ethmoidectomy. Discussion: Late diagnosis is harmful due to the fact that malignant disease is extremely aggressive and fast, as reported in this case. Most often, the ophthalmopathy follows a relatively mild and self-limiting course, making a proper diagnosis difficult if the disease progresses. In extreme cases acute orbital decompression is indicated complementing appropriate medical treatment, which will allow herniation of orbital contents. Many orbital decompression techniques have been used in the treatment of Graves’ ophthalmopathy. The most common of these is the endoscopic sinus surgery which potentiated act in decompression of the medial wall safely and minimally invasive. In our case, open bilateral ethmoidectomy was used, due to the fact that surgeons are most experienced in this technique. Although the post-operative has been successfully submitted, no signs of recurrence were observed after fifteen days due to the evolution of Graves’ disease. Even with outpatient treatment, he walked to the total visual loss. Conclusion: We observed that the malignant ophthalmopathy is rare and aggressive; however, in spite of therapeutic resources used, it can progress to total visual loss.