This study was conducted to identify the factors associated with weight control and nutritional knowledge of juvenile delinquents. The average heights of the subjects in this study were 172.20 cm (male) and 160.89 cm (female), and the average weights were 66.73 kg (male) and 58.42 kg (female), and the BMIs (Body Mass Index; kg/m2) were 22.46 (male) and 22.54 (female). The results of this study revealed that 41.4% of the subjects were over weight or obese. In addition, there were significant differences in the BMI, satisfaction with body image and perception of body image observed between male and female subjects. Furthermore, female subjects were more experienced at weight control than male students (p〈0.001). Additionally, overweight and obese individuals had more experience with weight control than subjects that were not overweight. Moreover, there were significant differences in the reason that subjects took weight control measured between male and female students. Specifically, female subjects practiced weight control due to their appearance (p〈0.001). The order of methods by which male subjects attempted to control their weight was exercise〉diet control〉starvation and for girl student were diet control〉starvation〉excercise. The nutritional knowledge scores were higher for female subjects than for mele subjects. In addition, the nutritional knowledge scores increased as the BMI value increased and the father˚Øs educational level increased. These results of this study could be useful data to plan and develop nutritional education programs for juvenile delinquents.