A pneumatic tire for two-wheeled motor vehicles 1 comprises a belt layer 7 and a tread reinforcing layer 9 outside of a single carcass ply 6A made of organic fiber cords. The belt layer 7 is comprised of a belt ply 7A in which steel cords are spirally wound substantially parallel to a tire circumferential direction. The tread reinforcing layer 9 is comprised of a reinforcing ply 9A in which organic fiber cords are aligned to be substantially parallel to the tire circumferential direction. A width RW of the reinforcing ply 9A in a tire axial direction is not less than 30 mm and not more than 90% of a tread grounding width CW.