Aortitis, in its simplest definition, is an inflammation of the aorta. It can be divided into two groups as infectious and non-infectious. Noninfectious aortitis can be an involvement of multisystemic and autoimmune diseases as well as being diagnosed incidentally. In our case, in which we planned elective coronary bypass surgery, we encountered an ascending aorta with a pearlish color, dilated and firm consistency intraoperatively. Histopathological examination showed extensive lymphoplasmocytic infiltration and strotiform fibrosis. In the laboratory tests performed for etiology in the postoperative period, no abnormalities were observed in the early and long term. Even when detected isolated and incidentally, aortitis may be a component of a multisystemic and/or autoimmune disease. The time of diagnosis may coincide with the asymptomatic period of the systemic disease. We wanted to present this case because it was detected incidentally during coronary bypass surgery and was diagnosed histopathologically immunoglobulin-G4 related aortitis, although it was not found in clinical and laboratory evaluations.