PROBLEM TO BE SOLVED: To simply perform a sterilizing treatment for a container such as a bottle in an in-line system.SOLUTION: A method for molding an aseptic container comprises: mounting a preform 1 heated in a mold 4 with a cavity C for the bottle 2 expanding the preform to an intermediate molded article 1a in the cavity and simultaneously sterilizing the inside of the intermediate molded article by blowing a mixed gas M in which a condensed mist or gas of hydrogen peroxide and air for primary blow are mixed into the preform expanding the intermediate molded article to a bottle in the cavity and simultaneously removing the hydrogen peroxide in the bottle by blowing air N for secondary blow into the intermediate molded article and preventing the deformation of a mouth part of the container by setting the temperature of a place corresponding to the mouth part of the container in a mold to be lower than that in a place corresponding to the center part of the container. Because the sterilization and the molding of the bottle are carried out at the same time, the sterilization treatment is easily executed.
