An object of the present invention is to provide an inclusion compound in which isohumulones are included in .gamma.-cyclodextrin (CD). According to the present invention, there is provided an inclusion compound of isohumulones which is obtainable by mixing isohumulones, .gamma.-cyclodextrin (.gamma.CD) and an aqueous solvent in a ratio of isohumulones:.gamma.CD:aqueous solvent=1:5 to 25:20 to 112.5, where .gamma.CD aqueous solvent=1:4 to 9.