The 297 middle school girls in Inchon were devided into three groups according to body mass index(BMI), the under weight group, the normal weight group and obese group to find out relationship between their food habits, food preference, and obesity. The average height and weight are 159.40cm, 67.02kg for obese group, 158.17cm, 39.11kg for under weight group, 156.93cm, 53.78kg for normal weight group. Obese group feels that they are healthy and fat, and their parents are fat also than the other groups. Obese group took more exercise. Total Food habits scores of obese group were lower than the other two groups. In terms of supper, bedtime-smack, unbalanced diet, balanced intake of five basic food groups obese group had lower scores. Especially, intake of carbohydrate, protein, milk group were irregular. There is no significant different in size of meal, overeating eating speed. The preferences of fast food, instant food, high caloric density food were lower in obese group than in the other two groups. The mother of obese group prepared meals according to food composition and prepared little snakes.