A straddle vehicle comprising: a prime mover; a hydraulically actuated main clutch disposed in a power transmission route between the prime mover and a drive wheel; an oil control valve unit that controls flow of a hydraulic oil supplied to the main clutch; a power unit case comprising a case body and a cover removably mounted on the case body, the power unit case accommodating at least the main clutch, wherein the oil control valve unit is secured to the case body, the main clutch comprises an inlet port into which the hydraulic oil is supplied, each of the case body and the cover comprises a hydraulic oil passage, and the oil coming out of the oil control valve unit flows through the hydraulic oil passage of the case body and then through the hydraulic oil passage of the cover to enter the inlet port of the main clutch, the prime mover comprises a drive shaft (Ea) having an axis extending in a vehicle width direction of the straddle vehicle, the power unit case comprises a main chamber accommodating the drive shaft (Ea) and a subsidiary chamber accommodating the main clutch, the subsidiary chamber being defined between the case body and the cover and located on one side in the vehicle width direction with respect to the main chamber, the case body comprises a side wall portion defining the main chamber and a frame-shaped wall portion projecting from the side wall portion and defining the subsidiary chamber, characterized in that: the frame-shaped wall portion comprises a lower edge portion, a front edge portion, and an inclined portion extending obliquely forward and upward from the lower edge portion to the front edge portion, the side wall portion has a mounting surface located forwardly of and below the inclined portion when viewed in the vehicle width direction, and the oil control valve unit is secured to the mounting surface of the side wall portion. a prime mover; a hydraulically actuated main clutch disposed in a power transmission route between the prime mover and a drive wheel; an oil control valve unit that controls flow of a hydraulic oil supplied to the main clutch; a power unit case comprising a case body and a cover removably mounted on the case body, the power unit case accommodating at least the main clutch, wherein the oil control valve unit is secured to the case body, the main clutch comprises an inlet port into which the hydraulic oil is supplied, each of the case body and the cover comprises a hydraulic oil passage, and the oil coming out of the oil control valve unit flows through the hydraulic oil passage of the case body and then through the hydraulic oil passage of the cover to enter the inlet port of the main clutch, the prime mover comprises a drive shaft (Ea) having an axis extending in a vehicle width direction of the straddle vehicle, the power unit case comprises a main chamber accommodating the drive shaft (Ea) and a subsidiary chamber accommodating the main clutch, the subsidiary chamber being defined between the case body and the cover and located on one side in the vehicle width direction with respect to the main chamber, the case body comprises a side wall portion defining the main chamber and a frame-shaped wall portion projecting from the side wall portion and defining the subsidiary chamber, characterized in that: the frame-shaped wall portion comprises a lower edge portion, a front edge portion, and an inclined portion extending obliquely forward and upward from the lower edge portion to the front edge portion, the side wall portion has a mounting surface located forwardly of and below the inclined portion when viewed in the vehicle width direction, and the oil control valve unit is secured to the mounting surface of the side wall portion. the frame-shaped wall portion comprises a lower edge portion, a front edge portion, and an inclined portion extending obliquely forward and upward from the lower edge portion to the front edge portion, the side wall portion has a mounting surface located forwardly of and below the inclined portion when viewed in the vehicle width direction, and the oil control valve unit is secured to the mounting surface of the side wall portion.