This study was conducted to explore socio-demographic influences on eating behaviors among adolescents in Korea. Data were obtained from the Eleventh Korea Youth Risk Behavior Web-based Survey (2015 KYRBS), a nationwide representative sample of 3,532,149 middle and high school students. The data were analyzed by descriptive analysis, t-test, and logistic regression based on complex sample design using SPSS 20.0 statistics. The results showed that intake frequency of soda, fast food, and instant noodles was higher in male than female students (P＜0.001). Additionally, the frequency of eating breakfast, fruits, vegetables, and milk was higher among high school students than middle school students (P＜0.001). Higher levels of economic status were associated with less skipping breakfast. Adolescents with mothers that had higher levels of education were more likely to be frequent consumers of fruits, vegetables, and milk, and to eat breakfast.