The present invention provides a foam-holding agent which has a sufficient foam-holding property and is satisfactory with regard to safety, taste, aroma and other properties required for foods, as well as providing effervescent drinks or forming beverage comprising the foam-holding agent. More specifically, the present invention is directed to a foam-holding agent for effervescent drinks or forming beverage, which comprises a tea leaf extract obtained by preparing tea in a standard manner from leaves of black tea, green tea, oolong tea, Gynostemma pentaphyllum tea, Mate tea, Pu-erh tea, barley tea, Coix lacryma-jobi var. ma-yuen tea, brown rice tea, Houttuynia cordata tea or other tea leaves, and then extracting catechin-rich components using a solvent such as water and/or ethanol. The present invention is also directed to effervescent drinks or forming beverage characterized by comprising the above foam-holding agent, which have excellent foam-producing and foam-holding properties and also provide dense and smooth-textured foam.