Purpose: Childhood obesity is one of the most severe public health problems in recent years. We aimed to compare physical fitness and activities of daily living (ADL)-participation limitations in adolescents with obesity and peers without obesity and investigate whether the differences in these parameters are affected by gender in this study. Methods: Fifteen adolescents with obesity and 16 adolescents without obesity included in this cross-sectional study. Physical fitness was determined using the Munich Physical Fitness Test (MFT) and Modified Shuttle Walk test (MSWT). ADL were determined using the TGlittre-P test, quality of life and participation was assessed using the Pediatric Outcomes Data Collection Instrument (PODCI). Results: The MSWT distance, peak oxygen consumption, and MFT total score were decreased in adolescents with obesity regardless of gender (p<0.05). TGlittre-P test time was significantly longer in girl adolescents with obesity than girls without obesity (p=0.019). PODCI-physical function and sports, happiness/satisfaction, and global function scores were decreased in adolescents with obesity compared to peers without obesity (p<0.05). Conclusion: Peripheral muscle strength, endurance, power and cardiorespiratory/physical fitness are negatively affected by obesity in adolescents. Gender affects the ADL performance and participation limitations increase due to restriction in sports and physical function, happiness, and global function in adolescent obesity. Further studies need to focus on the effectiveness of enjoyable and suitable activities or exercise interventions on these parameters and also cardiovascular risk levels in adolescents with obesity.