A method and apparatus for vulcanizing tires are provided. An unvulcanized tire is transferred and loaded onto a lower mold member when a plurality of arcuate sector mold members aligned along the peripheral direction locate at the radially outermost positions as well as upper ends of the sector mold members incline radially outwards about their lower ends. An upper mold member moves toward the lower mold member while the sector mold members are swung about their lower ends to straightly stand the sector mold members, and the sector mold members are then synchronously displaced radially inwards, so that the unvulcanized tire is hermetically enclosed in a mold space formed by these mold members. The unvulcanized tire is vulcanized within the mold space to give a vulcanized tire. The sector mold members are synchronously displaced radially outwards, and swung such that the upper ends incline radially outwards about the lower ends while the upper mold member is moved away from the lower mold member, so as to remove the vulcanized tire out of the mold.