Three or more independent passages are coupled to respective cylinders which are different from each other, and a collective portion where the independent passages collect is provided. An exhaust turbocharger is arranged downstream of the collective portion. Rotary throttle valves are arranged respectively in the independent passages upstream of the collective portion. At least two of the throttle valves are supported by a common rotary axis. The independent passages with the throttle valves supported by the common rotary axis are coupled to cylinders which have exhaust strokes which are not adjacent to each other. Accordingly, the exhaust gas can be supplied to the exhaust turbocharger efficiently.