PROBLEM TO BE SOLVED: To provide a new &alpha；-glucosidase inhibitor which has high safety and high activity and can easily be taken. SOLUTION: The &alpha；-glucosidase inhibitor is obtained by extracting the bran of modern rice or pigment-having rice with water, a polar solvent such as methanol, ethanol, propanol, 1,3-butylene glycol, glycerol, propylene glycol, ethyl acetate, or butyl acetate, a nonpolar solvent such as hexane, especially preferably water, an alcohol such as methanol or ethylene, or a mixture of water with the alcohol. The &alpha；-glucosidase inhibitor is provided as a processed food, such as the so called health food, obtained by adding the inhibitor to one of various foods or mixing the inhibitor with one or more additives and then processing the mixture into tablets or the like, or as a hyperglycemia medicine. The &alpha；-glucosidase inhibitor may be added as an additive comprising a saccharide or added to a feed for pets or livestock.
