PURPOSE: The titled boiled rice prepared by extracting Polygonum cuspidatum and adding to rice during cooking rice is provided, which is nutritionally strengthened by adding glucoside, amino acid, starch or the like, and has a delicate flavor peculiar to Polygonum cuspidatum. CONSTITUTION: In cooked rice obtained by adding water to rice or miscellaneous cereals in an amount of 1.1 to 1.8 times, dried Polygonum cuspidatum is dissolved in water in an amount of 15 to 20 times at 80 to 90deg.C for 10 to 15 hr, added with 30 to 50% by volume of Polygonum cuspidatum extracts in place of water, and heating at 100deg.C for 20 min.
