Objectives: The aim of this study was to determine the relationship between depression, anxiety and stress levels and socio-demographic characteristics of overweight and obese adolescents. Methods: The sample of this cross-sectional study was 206 adolescents aged between 10 and 13 years who were overweight and obese in four secondary school in Istanbul. The data were collected by using ”Socio-Demographic Characteristics Form”, “Beck Depression Inventory”, “Beck Anxiety Inventory” and “Stress Management Subscale of Adolescent Life Style Scale” Descriptive statistical analyzes were based on percent, mean, standard deviation, minimum and maximum; Kolmogorov Smirnov test was used for the data normalization, and comparative analyzes were performed using the Kruskall Wallis varyans analizi, T-Test and Mann Whitney-U Test. Results: According to the findings of the study, high stress, moderate depression and severe anxiety were determined in overweight and obese adolescents. Depression and anxiety levels were found to be significantly higher in overweight and obese adolescents whose fathers were primary school graduates compared to university graduates. In overweight and obese adolescents with a chronic disease, stress levels were significantly higher than those without stress. Conclusion: The results of this study showed that there is a significant relationship between obesity and depression, anxiety and stress, and it is also recommended to include stress management interventions in adolescent obesity prevention programs.