Coarse grain crops including maize, sorghum, buckwheat, fox-tail millet, pearl millet, proso millet and barnyard millet have been used as health food, feed and industrial materials in Korea for a long time. Korean ancestors thought and treated them as the very important good crops for human health and the crops have served as a dish made with all the grains, particularly in January 15 of the lunar month in korea because the grains make the five viscera of heart, liver, spleen, lungs and kidneys and the six entrails of gall bladder, stomach, small and large intestines, the paunch, the bladder, and the bowels strong and build healthy body. Thus, the objectives of the paper were to review and summarize the results obtained from the quality breeding and functional researches worldwide on nutrition, utilization and medical action of the coarse grain crops. Maize grain, fresh ear and green fodder yields have increased since 1960s in Korea. Agronomic traits improvements also occurred for cold tolerance, disease and insect resistance, resistance to barrenness, resistance to loding, pollen production, grain and seed yields, and eating quality. For buckwheat, improved summer buckwheat varieties produced more rutin for vegetable and grain than autumn varieties in Korea