After loading a green tire in a tire vulcanizing machine and before shaping, bead portions of the green tires are centered relative to bead rings of upper and lower metal molds and are sequentially inserted into the bead rings precisely in parallel thereto by the same extendable/retractable sectors and chucks which are movable vertically. An apparatus preferable for practicing the aforementioned method includes a plurality of such sectors for centering and holding a bead portion of the green tire, slide and linkage mechanisms for extending and retracting chucks to which the sectors are mounted, and a cylinder mechanism for vertically moving the chucks so as to insert the bead portion of the green tire centered and held by the sectors into a bead ring of a tire metal mold.