A drink filling method comprising the steps of: preheating a preform, blasting hydrogen peroxide mist or gas to the preheated preform, and further heating the preform to a temperature suitable for molding the preform, the above-mentioned processes being performed in a state of the preform while being continuously travelled; molding the preform into a container in a blow-molding mold which is also travelling together; taking the container out of the blow-molding mold; and filling the container with drink (a) and then sealing the container with a cap while the container being continuously travelled, wherein all the steps from the preheating of the preform to the heating of the preform to the temperature suitable for the molding step are performed within a heating furnace, having a furnace room extending in one direction, wherein inside the furnace room, an endless chain is stretched between a pair of pulleys (51a, 51b) arranged oppositely in a horizontal plane, wherein the endless chain constitutes an endless conveyer, together with associated members, that conveys a number of preforms in a suspended state, and wherein infrared heaters are attached to an inner wall surface of the furnace room along an outward path and a return path of the endless chain, wherein the outward path and the return path form a preform conveying path in the heating furnace, wherein hydrogen peroxide supply means for blasting hydrogen peroxide mist or gas to the preform are disposed at a substantially middle portion of the preform conveying path in the heating furnace, at a position in the vicinity of one pulley, which turns the endless chain from the outward path to the return path, and wherein, when the preform is conveyed into the heating furnace, the preform is preheated to 40 to 80°C by the infrared heaters while being conveyed along the outward path of the endless chain, the preform is then subjected to blasting of the hydrogen peroxide mist or gas, and the preform is heated to the temperature suitable for the molding along the return path. preheating a preform, blasting hydrogen peroxide mist or gas to the preheated preform, and further heating the preform to a temperature suitable for molding the preform, the above-mentioned processes being performed in a state of the preform while being continuously travelled; molding the preform into a container in a blow-molding mold which is also travelling together; taking the container out of the blow-molding mold; and filling the container with drink (a) and then sealing the container with a cap while the container being continuously travelled, wherein all the steps from the preheating of the preform to the heating of the preform to the temperature suitable for the molding step are performed within a heating furnace, having a furnace room extending in one direction, wherein inside the furnace room, an endless chain is stretched between a pair of pulleys (51a, 51b) arranged oppositely in a horizontal plane, wherein the endless chain constitutes an endless conveyer, together with associated members, that conveys a number of preforms in a suspended state, and wherein infrared heaters are attached to an inner wall surface of the furnace room along an outward path and a return path of the endless chain, wherein the outward path and the return path form a preform conveying path in the heating furnace, wherein hydrogen peroxide supply means for blasting hydrogen peroxide mist or gas to the preform are disposed at a substantially middle portion of the preform conveying path in the heating furnace, at a position in the vicinity of one pulley, which turns the endless chain from the outward path to the return path, and wherein, when the preform is conveyed into the heating furnace, the preform is preheated to 40 to 80°C by the infrared heaters while being conveyed along the outward path of the endless chain, the preform is then subjected to blasting of the hydrogen peroxide mist or gas, and the preform is heated to the temperature suitable for the molding along the return path.