Objective: The aim of this study was to evaluate the prevalence of energy drink consumption and its effects on perceived stress and sleep quality among high school students. Material and Methods: In this cross-sectional study was conducted with 2806 students. The first part of specific survey investigated the sociodemographic characteristics and the energy drink consumption habits of students. The perceived stress scale and the Pittsburgh Sleep Quality Index (PSQI) were performed. Results: The mean age of students was calculated as 15.73 ± 1.16 years. It was revealed that prevalence of energy drink consumption was 70.8%. Male sex, being a member of divorced family, irregular sleep habits, and believing that energy drinks are unhealthy & addictive were found to be significant factors affecting the frequency of energy drink usage. The mean score of the students' Perceived Stress Scale was 28.95 ± 7.22 and the mean score of the PSQI was 6.56 ± 2.84. Perceived Stress Scale and PSQI scores of consumer students were higher than non-consumers. Conclusion: Energy drink consumption was found to be quite frequent in the study group. Consumption of energy drinks negatively affected the level of stress and sleep quality. Educational programs should be provided to students on the harmful effects of these beverages.