There is provided an ingredient of a tea drink which ingredient makes it possible to manufacture a tea drink that has a novel aroma and taste and that produces no unpleasant flavor associated with a heat treatment. The ingredient for a tea drink is manufactured by a method including the steps of impregnating a tea drink ingredient with an amino-acid solution that contains at least one amino acid selected from the group consisting of leucine, valine, and isoleucine, and heating the tea leaves at a temperature of 100 to 200°C.