Background: People may develop addiction to hyperpalatable foods, which may be a cause of obesity. This study aimed to determine the prevalence of obesity among adolescents and the effect of food addiction on obesity. Materials and Methods: In this cross-sectional study, food addiction and obesity status of high school students were investigated. Among 17,000 10th and 11th grade students, assuming the design effect as 2.0, with obesity prevalence of 10%, with 3% error, and 95% confidence interval, at least 752 participants were included. Obesity was the dependent variable, whereas sociodemographic characteristics, body image, eating habits, and food addiction were the independent variables. Food addiction was assessed using the Yale Food Addiction Scale. Obesity was determined by age- and sex-specific body mass index (BMI) percentiles for adolescents < 18 years of age and BMI >= 30.0 for those aged >= 18. Data were collected through face-to-face interviews. Statistical analyses were performed using SPSS 25.0. After adjustment for age, sex, and other variables, the effect of food addiction on obesity was determined through logistic regression. P <0.05 was deemed statistically significant. Results: Among adolescents (n = 874), 18.9% were food addict, 25.1% were overweight, and 12.1% were obese. After adjusted for age, sex, and other variables, food addiction significantly increased the risk of obesity (odds ratio: 1.9; 95% confidence interval: 1.167-3.335). Having a fragmented family, working mother, overweight father, and participants not knowing their weight correctly significantly increased obesity. Conclusion: While quarter of the adolescents had weight problems, one-fifth suffered from food addiction. After adjusting for confounders, food addiction significantly increased obesity. Identifying individuals with food addiction, providing treatment to overcome that, paying special attention to adolescents with obese parents or living in fragmented families, and providing support to both parents and adolescents could be useful in tackling obesity.