Disclosed is a highly flexible blow molding machine capable of easily saving space of a conveying path for molded articles and reducing time loss while improving the productivity by conveying the molded articles in a plurality of lines. Specifically disclosed is a blow molding machine which comprises an injection molding station (12) at which a plurality of preforms (1A) held by holding plates (30) arranged in N (N is an integer more than or equal to two) lines are injection molded; a temperature control station (14) at which the temperature of the preforms (1A) is controlled; a blow molding station (16) at which the plurality of preforms are blow molded into a plurality of containers; and a line pitch conversion driving unit (130) that converts the line pitch of the holding plates arranged in N lines such that a relation P1 < P3 < P2 is satisfied, where P1 is a line pitch of the holding plates arranged in N lines holding the plurality of injection molded preforms, P2 is a line pitch of the holding plates arranged in N lines holding the plurality of blow molded containers, and P3 is a line pitch of the holding plates arranged in N lines holding the plurality of preforms to be carried into opened blow molds arranged in N lines.
