Dissection of the interventricular septum (IVS) is an extremely rare entity. The patients with venticular septum dissection have been reported before. Most cases were diagnosed with coronary artery disease, Bechet’s disease or injury. However, we will report the case not linked to them and treated by aortic valve repair. It may be the first case of spontaneous contained aortic annulus rupture with dissection of IVS, which was successfully treated by surgery.