Provided is a pneumatic tire where a main groove extending in a tire circumferential direction and a projection projecting toward the inside of the main groove from a groove side wall of the main groove are formed on a tread portion, wherein a projecting amount of the projection from the groove side wall is decreased as the projection extends to a groove bottom of the main groove, the projection terminates at a position outside the groove bottom in a tire radial direction, and a length of the projection along the tire circumferential direction is shortened as the projection extends to a distal end side of the projection in a projecting direction.