In the early part of this century, largely stimulated by the covincing anatomical studies of Onodi(1904-8) and Loeb(1909) in America, a considerable body of opinion contended that most cases of optic and retrobulbar neuritis were secondary to infections of sinuses. Despite of a close anatomical relationship between sinuses and orbit, there has never been a report concerned with optic neuritis secondary to sinus infections in our conutry. We believe it very important to deal with this disease in E.N.T. field, when neglected, there may be a danger of blindness. Recently the authors have experienced a case of optic neuritis due to sinus infections in a 25 years old male patient and so report with some reviews of the literatures.