Overweight and obesity in children and adolescents are highly prevalent and persistent. Current weight loss treatments are rarely individualized and show only small to moderate efficacy. Only rarely, psychopathological parameters are considered. The present study evaluated the psychopathology of adolescents with overweight and obesity (N=201, ages 12-17 years) prior to obesity treatment. The data were analyzed for age and sex effects. Self-report questionnaires assessed general symptom burden, eating disorder and general psychopathology, weight-related self-stigmatization, and physical and mental quality of life. Girls showed higher rates of weight-related self-stigmatization and higher disordered eating behavior compared to boys. Older adolescents reported a lower quality of life compared to younger adolescents. In normative comparisons with population-based samples and norms, adolescents with overweight and obesity showed significantly adverse outcomes in all parameters. Thus, this study identified psychopathology as an important factor in adolescents with high weight status that may affect obesity treatment. Future studies should examine psychopathology more differentially and determine therapeutic resources in adolescent overweight and obesity.