Provided are a piceatannol-containing composition which is a composition originating in a natural material and containing piceatannol at a high concentration, and a method of producing the piceatannol-containing composition. A piceatannol-containing composition which contains 0.0001 to 99.9% by mass of piceatannol is obtained by extracting passion fruit seeds. The extraction of piceatannol is carried out by grinding the passion fruit seeds, adding at least one solvent selected from an aqueous alcohol-based solvent and an aqueous ketone-based solvent and agitating to thereby extract piceatannol into the above-described solvent. In this case, it is preferable to conduct stepwise extraction by using both of the aqueous alcohol-based solvent and the aqueous ketone-based solvent.