One ends of an exhaust path communicate with a plurality of combustion chambers through exhaust ports, respectively, an assembling section is provided on the other ends of the exhaust path, and a turbo supercharger, an exhaust tube and an exhaust purification catalyst are connected to the assembling section, on the other hand, a bypass path communicating from the exhaust path to the exhaust tube and the exhaust purification catalyst by bypassing a turbo supercharger is provided and an exhaust control valve capable of opening and closing the bypass path is provided, and a bypass hole, which is a part of the bypass path, is provided in the cylinder head.