The purpose of the present invention is to provide a novel drug comprising a variety of active ingredients having an action of inhibiting protein carbonylation. The protein-carbonylation inhibitor comprises one or more active ingredients selected from olive leaf extract, hydrolyzed pea protein, and lemon extract.本發明之目的在於提供一種含有具有抑制蛋白質之羰基化之作用之各種有效成分而成的新穎之藥劑。本發明係一種含有選自橄欖葉萃取物、水解豌豆蛋白及檸檬萃取物中之一種或兩種以上之有效成分而成之蛋白質羰基化抑制劑。