This study was performed to evaluate the effectiveness of a nutrition education program developed for nutritionally imbalanced adolescents. A summer nutrition camp was held for 23 overweight and 16 underweight subjects. Its effectiveness with regard to was evaluated at the end of the camp and 6 months later. Nutrition knowledge, nutritional attitude, food behavior, nutrient intake, exercise habit and ideal body figures desired by the subjects. The results showed significantly higher nutrition knowledge scores at the end of the camp as compared to those obtained prior to the camp program, and these scores were maintained for at least six months. Nutrition attitude scores also improved after the education program, and these improved scores also lasted for 6 months. However, the food behavior scores measured 6 months after the education program were not significantly different from those obtained prior to the camp. Also, the exorcist habit, the ideal body figures and the body figures desired by the subjects remained unchanged. When nutrient intakes of subjects were assessed before the program and 6 months later, the mean daily vitamin C intake was significantly increased after the education program. Also, the intake of iron from plant food sources increased in the overweight subjects, while less iron from animal source were consumed by the underweight subjects. Both groups tended to consume more vegetables and fruits 6 months after the education program which may have contribute to the higher vitamin C and plant-based iron intakes. These results indicate that a 4-day nutrition education camp program sustained changes in nutrition knowledge and nutrition attitude for 6 months. The increased intake of vegetables and fruits was also achieved through this education program. However, changes in dietary behavior in adolescents may require repeated education. (Korean J Community Nutrition 8(4) : 504-511, 2003)