PROBLEM TO BE SOLVED: To provide a new polymerized compound of resveratrol having a physiological activity more forceful than that of resveratrol, a method for efficiently and safely producing the polymerized compound of resveratrol, and an anticancer agent, an antioxidant, an antimicrobial agent, a foodstuff, pharmaceuticals, a quasi-drug, and a cosmetic each comprising the polymerized compound of resveratrol.SOLUTION: There are disclosed a dimer of resveratrol, a pharmacologically acceptable salt, ester and ether thereof, and an anticancer agent, an antioxidant, an antimicrobial agent, a foodstuff, pharmaceuticals, a quasi-drug, and a cosmetic, each comprising at least one species of compounds selected from the group consisting of the dimer of resveratrol, and a pharmacologically acceptable salt, ester and ether thereof.
