This study was designed to observe the nutritional knowledge, dietary life, and health condition in the middle school students. The subjects of this study were sampled out from co-ed middle schools in Seoul. The results of this study are summarized as follows: 1. The subjects take breakfast everyday by 50.4%, and their lunch depends very largely upon a lunch box by 95.2%. They take supper every evening by 79.0%. 2. The nutritional knowledge of subjects exhibits a significant difference by sex and region 3. The physical health condition of students exhibits a significant difference by sex and grade. 4. The mental health condition of students also exhibits a significant difference by sex, grade, and region. The school is required to endeavour for the student to have a correct understanding of nutritional knowledge form good dietary life. The government also should exert incessant efforts for school meal supply for their balanced nutrition.