To provide a lightweight compact vehicle by installing a supercharging device by which complication of a structure and increase in a size of the whole of a device can be avoided.

An engine unit 17 constructed by integrating an engine main body, which introduces fresh air pressurized by means of a supercharger 22 to a combustion chamber via a pressurized intake passage, an intake port, an intake valve in the intake port end part and discharges emission gas to the atmosphere via an exhaust valve, an exhaust port, and an exhaust passage, and a rear shaft transmission device 18 together is mounted in a vehicle body swingably. An air cleaner 35, which is arranged on the upstream side of the supercharger 33 so as to filtrate the fresh air, is installed in the engine unit 17, and the air cleaner 35, the super charger 33, and the pressurized intake passage can be swung with the engine unit 17.