The shapes of the upper tire bead Bu and the lower tire bead Bl of a green tire G and the axial distance between the tire beads Bu and Bl are corrected in a short work time. The green tire G is placed in horizontal attitude on a green tire support table 3 provided with a lower tire bead correcting unit 10. Radially movable pressing members 13 included in the lower tire bead correcting unit 10 are engaged with the inner side of the lower tire bead Bl of the green tire G and stoppers 29 of the upper tire bead correcting unit 20 are engaged with the inner side of the upper tire bead Bu of the green tire G placed on the green tire support table 3. The pressing members 13 of the lower tire bead correcting unit 10 are moved radially outward to shape the lower tire bead Bl into a completely round shape of a predetermined diameter. The stoppers 29 of the upper tire bead correcting unit 20 are moved radially outward to shape the upper tire bead Bu into a completely round shape of a predetermined diameter and, at substantially the same time, the upper tire bead correcting unit 20 or the lower tire bead correcting unit 10 is moved vertically to adjust the axial distance B between the tire beads Bu and Bl to a predetermined axial bead spacing.