To provide a method suitable for manufacturing a light plastic container having a thin and slender cylindrical barrel.

The manufacturing method of a plastic container having a cylindrical barrel 2, a bottom 3 and a tip section 4 comprises: a step (ST1) wherein a preform 11 in which the bottom 3 and the tip section 4 are already formed to both ends of a thick cylindrical barrel 12 thicker than the cylindrical barrel 2 and short is manufactured by the injection molding; a step (ST2) wherein the thick cylindrical barrel 12 of the preform 11 is heated to the temperature suitable for the extension blow; and a step (ST3) wherein the extension blow of the heated portion of the preform 11 is carried out to mold the plastic container 1 having the thin cylindrical barrel 2 with the last length.