To evaluate the effect of cereal supplementation on children's iron nutritional status of Korean institutionalized was designed. Dietary survey was carried out methods of food weighting in the breakfast or/and dinner, and record interview in lunch (n=74). A nutritional intervention study was carried out through supplementing cereal for 4 weeks in 24 children of 1 institution from 4 to 12 years. The children received 3.6mg elemental Fe(as 100g cereal) per day. Blood samples were drawn before and after supplementation. Nutrients which children's intake was less than two-thirds of Korean RDA were Vit A, Vit B1, Vit B2, Ca and Fe. The mean daily intakes of iron were 5.1mg for male and 4.9mg for female and 52.3% for male and 45.4% for female of Korean RDA. The proportions of children with iron depletion assessed by TIBC(>360mg/dl) and serum ferritin(<20ng/ml) were 56.6% and 58.7%, respectively. The proportions of children with the iron deficient erythropoiesis assessed by serum iron(<70ml/dl), Hb(<12g/dl), and Hct(<36%) were 76.0%, 58.7%, and 64.0%, respectively. After cereal supplementation, in anemic children, levels of Hct(p<0.001), serum iron(p<0.001) and transferrin saturation(p<0.001) were significantly increased. The effect of cereal supplementation in children with iron deficient erythropoeisis was more effective to improve the iron nutritional status than children with iron depletion. It was concluded that cereal supplementation program in anemic children was also effective to improve iron nutritional status.