To make a sterilization step appropriate in an aseptic filling apparatus. Provided is an aseptic filling apparatus including a step of sterilizing a preform and a step of sterilizing a container obtained by molding the preform, wherein assuming sterilization effects in the respective sterilization steps as X [LRV] and Y [LRV], a relationship of 5≤X+Y≤10 (where Y≥0) is established.