[Problem] To realize a predetermined “aseptic level of the containers” without introducing a container sterilizing machine and to reduce the burden for adjusting the temperature of the preform.[Means for Solution] A metal mold for molding, wherein a space width (t2) of at least the body portion in the space width for forming a thickness of from the body portion to the bottom portion of the preform is set to lie in a range of 1.18 to 2.11 times as great as a space width (t1) for forming a thickness of an upper end portion of the mouth portion of the preform. At the time of the compression molding, the preform is taken out in the state of a high temperature from a compression-molding machine 31 and is fed to a bottle-producing unit C while maintaining the state of a high temperature. Further, the inner surfaces of a clean box I in which the units are placed and the outer surfaces of the units are sterilized, and the interior of the clean box I maintains a positive-pressure state with the filtered clean air. The bottle-producing unit C and a filling/sealing unit D are neighboring and directly coupled to each other in the same clean box, and are partitioned by a WBZ 54.