Prevalence of childhood obesity is increasing significantly worldwide due to energy imbalance perhaps stemming from undesirable dietary behavior and physical activity level. The objective of the study was to examine the effects of physical activity level on nutritional status in elementary school students. The subjects were comprised of 287 elementary school students between 4th and 6th grades in Seoul, Korea. The level of physical activity was scored with a modified Godin leisure-time exercise questionnaire and was categorized as active, moderately active, and sedentary. Dietary intakes were obtained using a 24-hour food recall method. An analysis of variance (ANOVA) was conducted to test for global significant differences of nutrient intakes by physical activity level. Boys were more active than girls. Daily intakes of energy in moderately active boys were significantly higher than in the sedentary group, but intakes of calcium and iron in moderately active boys were lower than active boys. For girls, physical activity level did not affect nutrient density at all. Intakes of calcium, vitamin C, and folate for both boys and girls were below 50% of recommended intake. Physical activity did not affect nutrient density and our participants were exposed to nutritional imbalance. Therefore, the results suggest that nutrition education regarding balanced diet and optimum physical activity is required for children's health and growth.