PROBLEM TO BE SOLVED: To provide a novel anti-obesity agent which has more remarkably excellent anti-obesity function than catechins alone, and in which the bitter taste of catechins and caffeine is suppressed, and to provide foods, medicaments, and quasi drugs containing the anti-obesity agent.SOLUTION: Disclosed are an anti-obesity agent composition in which the bitter taste of gallate type catechin and caffeine was reduced, and foods, medicaments, and quasi drugs containing the anti-obesity agent characterized by being a solid form composition obtained by adding caffeine before and/or after drying colloidal liquid formed in the range where the ratio (B/A) of the content (% by weight) of protein (B) having 4,000 or more average molecular weight to gallate type catechin (A) is 1-20.
