This study was designed to investigate body image, objective and subjective measurements of body size and shape, eating behavior, and weight control practices in 650 Korean adolescent girls; 500 of the subjects were 14 years old and enrolled in middle schools, while the remaining 150 were 17 years old and enrolled in high schools. Subjects responded anonymously to a self-administered questionnaire. The results showed that average height and weight of the subjects were 157cm and 49.5kg, respectively, while subjects ideal heights and weights averaged 164cm and 48kg, respectively. The ideal adult body heights and weights proposed by the subjects averaged 172cm and 55kg respectively. Over 50% of the subjects were dissatisfied with their body image; the degree of dissatisfaction with body image was higher in those who believed themselves to be fat. Most of the subjects wanted to lose weight and had tried to lose weight. Self-reported weight control practice methods included reducing food intake (31.9%), skipping meals (29.6%), exercise (25.8%), using slimming machines (6.9%), and using diet pills (5.1%). The heavier the subjects weight was, the greater the difference between the subjective and objective evaluations of body size. The body image scores of subjects who perceived themselves as fat were significantly lower than those of subjects who perceived themselves as normal or underweight. The difference between subjective and objective evaluations of body size, and the degree of obesity, were significantly higher in those subjects who had experience of weight control than those who had no experience of weight control. These results suggest that nutrition and health education programs for adolescent girls should be researched and implemented in order to establish a more realistic body image, positive habits in weight control, and healthful eating habits.