Pneumatic tire and method of manufacturing the same

In a pneumatic tire in which axial grooves (14,14s) are arranged on an outer surface (2S) of a tread portion (2) so as to be spaced apart from each other in a tire circumferential direction, a rib-forming region (Y) including at least one inward rib (15,15a,15b,15c) which projects from an inner surface (IS) of the tread portion inwardly in a tire radial direction and extends in a direction intersecting the axial grooves and across axial groove-inward regions (14Y) inward of the axial grooves (14,14s) in the tire radial direction is provided in the inner surface of the tread portion.