This study was conducted to investigate the correlation between frequency of high-caffeine energy drink intake in adolescents and their mental health status using data from the Korean adolescent health behaviors online survey (2014-15). Mental health was classified by the five categories: Perception of stress (PS), Insufficient relief of fatigue after sleep (IRFS), Experience of sadness despair (SD), Suicidal ideation (SI), and Subjective unhappiness (SU). Regarding general characteristics, higher age, height, and body weight of subjects were associated with higher frequency of high-caffeine energy drink (HCED) intake (p< .0001). In the OR analysis, when the lowest group (≤2/wk) and highest group (1≥day) were compared, the highest group showed significantly higher OR in all five categories of mental health. According to gender, males did not show better PS, SD, and SI than females who had a high frequency of HCED (p for trend<.0001). According to school level, middle school students showed a higher risk rate than high school students in PS, IRFS, and SD (p for trend< .0001). Based on the above results, higher frequency of HCED intake among adolescents was associated with more adverse effects on mental health.