Scleral inflammatory disease, a relatively common disease of the eye, is demonstrable on CT. Because of its unilateral and sometimes focal involvement, it may be mistaken for more serious diseases, both clinically and by CT. In particular, the clinical difficulties in diagnosing posterior scleritis have led to enucleations when such entities as melanoma and metastasis were suspected. We report the CT appearance and differential diagnosis of scleritis and correlate them with its clinical manifestations, both within the eye and systemically. We found CT to be reliable in differentiating scleritis from true choroidal and retrobulbar masses.