Objective: To investigate the situation of health-related main factors of Korean middle school adolescents. Methods: Data were collected via a self-reporting questionnaire from 2,254 students (650 boys and 1,604 girls), and their sleeping, exercise, dietary pattern, stress, physical problems, and taking of food supplements were analyzed. Results: Korean middle school students sleep about 7 hours per day, and they exercise less than 4 hours per week. Around 13% of the students skip breakfast nearly every day. 35% of the students were under severe stress, and 38% have reported at least one symptom of physical distresses including gastrointestinal disorders or headaches. 31% of the students took a functional supplement, especially one with vitamins as the most favored one, and ginseng and herbal drugs coming second and third. Conclusion: This result first reports a general feature of health-associated factors in middle school students. This study in the future will be basic information to develop medical supports for adolescents using traditional Korean medicine.