Purpose: This cross-sectional study was conducted to determine the risk factors which affect obesity in preadolescents. Materials and Methods: The sample of the study consisted of 500 preadolescents (girls: n=271, boys: n=229) attended in 18 secondary schools in the Cappadocia region of Turkey, and their parents. Data were collected using a questionnaire, the body weight, height, and waist circumference of the preadolescents were measured; the body mass index (BMI) and the waist-toheight ratio were calculated. Results: Of preadolescents; 14.4% were obese, 11.4% were overweight, 35.2% had abdominal obesity, and 27% had likehood of being at high metabolic and cardiovascular risk based on their waist/height ratio. According to the results of binary multiple logistic regression analysis (the backward stepwise procedure), the presence of an obese person in the family (boys), mother's educational level (girls), leisure time activities (girls), and an increase in eating according to mood (girls) were revealed as significant predictors of being overweight/obese, adjusted for age. Satisfied with current body weight and mother’s BMI were the strongest variable to be associated with overweight/obese for both genders. Conclusion: For early diagnosis and prevention of obesity in childhood, it is recommended to perform height-weight monitoring of students regularly, monitor risky children more frequently, provide training and consultancy for students and parents regarding balanced diets and physical activity, and provide the school-family cooperation.