This study investigated the food habits of the elementary school children according to obesity index. The subjects included 1,307 elementary school children classified into four groups according to their individual obesity indices: underweight, normal weight, overweight, and obesity. The distribution of subjects by BMI was 51.5% underweight, 32.9% normal weight, 7.3% overweight, and 8.3% obese. Of these children, 62.6% ate breakfast everyday, and common weight control methods were exercise and diet. Lack of appetite was the most common reason for skipping breakfast(75.3%). Most students(74.7%) had Korean traditional cooked rice and side dishes for breakfast, and 69.6% of students responded that their meal speed was $10{sim}30$ minutes. In conclusion, the food habits influencing obesity were eating speed, snack intake after dinner, and the number of snacks, while the size of meals did not influence obesity.