Provided is a method for producing a packaged beverage that makes it possible to suppress deterioration of the taste, flavor, appearance, and the like of a drink liquid due to heat applied during the production process or due to the effects of oxidation caused by dissolved oxygen in the drink liquid, the packaged beverage having an exceptional taste-flavor balance and a low environmental burden that makes it possible to reduce energy costs required during production. Such a production method is characterized in being provided with: a primary heating-deoxygenation step for heating a raw material solution by mixing together a raw material solution containing one or more plant extracts, and water at a higher temperature than that of the raw material solution, and adjusting the amount of dissolved oxygen in the mixed solution of the raw material solution and water; and a secondary heating-sterilization step for heating the mixed solution to the sterilization temperature thereof and maintaining this temperature fo
