It is intended to provide a process for producing a packaged drink whereby filling can be performed at room temperature without resorting to using a chemical or sterile water, the favorable taste and flavor of the content can be maintained while relieving the thermal degradation thereof, it becomes unnecessary to employ a heat-resistant container or to thermally sterilize or cool after sealing, and thus both of the equipment cost and the running cost can be largely reduced. After thermally sterilizing the content to give a definite sterilization value, it is quickly cooled to room temperature and then stored in a storage tank that has been preliminarily sterilized under such conditions as being equal to or exceeding the thermal sterilization conditions for the contents. While maintaining the storage tank under positive pressure with the use of a sterile gas, the content is fed into a filling machine that has been preliminarily sterilized under such conditions as being equal to or exceeding the thermal sterilization conditions for the contents. Thus, the liquid-feeding system ranging from the storage tank to the filling machine is made a closed liquid-feeding pathway free from the invasion of air from the outside. The drink is filled into a container having been sterilized with hot water in an environment-controlled space isolated from the outside wherein the surroundings have been thermally sterilized and washed with hot water at 65° C. to 100° C.