An economical process for producing a milk-added coffee beverage with an enhanced flavor in a process for producing a milk-added coffee beverage produced through a step of heat sterilization of coffee and milk as the main raw materials. The process includes adding a strongly basic substance and/or basic amino acid to the coffee component and conducting the heat sterilization after the milk component is admixed to the coffee component. Coagulation at the step of admixing milk component is prevented and precipitation which tends to arise after the heat sterilization is prevented with the use of a much smaller amount of emulsifier and thickening agent.