This method for producing a flavonoid clathrate includes a detachment step in which a poorly-soluble flavonoid having a rhamnoside structure is treated with an enzyme having rhamnosidase activity in the presence of cyclodextrin, to detach rhamnose. This production method allows efficient production of a highly water-soluble flavonoid clathrate and flavonoid glycoside composition, and can be favorably used in fields such as pharmaceuticals, foods and beverages, health foods, foods for specified health use, and cosmetics.