This study was performed to Investigate the nutritional knowledge and dietary patterns of 450 high school girls in some areas of Seoul. The survey conducted from September 20 to 25, 1993. The results obtained were summarized as follows ; The average height and weight of the subjects were 160.2$\pm$5.Ocm and 52.3$\pm$6.7kg respectively. The average obesity index of the subjects was 96.8$\pm$11.7%. Menarche was at 13 years of age in 35.6% of the subjects and at after 14 years of age in 37.3% of them. The average score of nutritional knowledge was 60.04 $\pm$ 14.49 and the average score of Perceived nutritional knowledge was 83.9$\pm$ 14.44. The mean score of nutritional knowledge was 49.61 $\pm$ 13.45. 35.6% of subjects ranked lecture of score as their primary sources of nutritional information. Major dietary problems of subjects were eating rapidly, skipping breakfast, unbalanced Inlet and choice of snacks according taste. Underweight group showed significantly higher than other groups In unbalanced diet(P<0.01) and showed significantly higher than other groups in taking a medicine(P<0.001). Obese group showed significantly lower than other groups in remaining meals and unbalanced diet (P<0.05) and showed significantly higher than other groups In voereating.