A power unit for a vehicle including a clutch capable of making and breaking the transmission of power to a drive wheel. The clutch is interposed in the course of a power transmission path, along which rotational power of a crankshaft is transmitted to the drive wheel. The clutch is rotatably borne on a crankcase, and its axis is set along the front-rear direction of the vehicle. A clutch actuator is provided for controlling the connection and disconnection of the clutch. The clutch actuator mounted to an engine body including the crankcase. This arrangement of the clutch actuator eliminates a need to increase the front-to-rear length of the engine and the vehicle body.