A tire vulcanizing apparatus includes a mold having a tread mold including a plurality of segments arranged in a tire circumferential direction, and upper and lower side molds. Each of the segments includes an upper segment portion and a lower segment portion which are divided up and down. The apparatus includes a segment supporting unit which supports the upper segment portion and the lower segment portion so as to be movable to the same side in a tire radial direction and opposite sides to each other in a tire axial direction.