Background and Aim: The increasing prevalence of overweight and obesity has become a major public health problems in both developed and developing countries among children and adolescents and health and psychological consequences can be extended. Thus, the aim of this study was to investigate the epidemiology of obesity and overweight in children 7 to 12 years old in the city of Sanandaj is the academic 2013- 2014. Material and Methods: This descriptive-analytic study was performed on 614 students aged 7 to 12 years in Sanandaj City schools. Required data was collected through interviews. Height and weight were measured using standard methods and body mass index (BMI) by dividing weight by the square of height in meters squared was calculated. Grouping measure of body mass index for age and sex cut proposed by the World Health Organization. Collected data were analyzed by SPSS software version 21. Results: The prevalence of obesity and overweight, 9.8 percent and 13.2 percent of students, respectively. 1.6 percent of students attended to school without having breakfast and 13.8 percent of them attend with irregular breakfast eating. There was a significant relationship between overweight and obesity and gender, father's level of education and breakfast(P <0.05).But no significant relationship was found between obesity and overweight with age, mother's level of education, parental occupation and consumption of junk food. (P >0.05) Conclusion: According to these findings, the prevalence of overweight and obesity students in Sanandaj, are on warning aspect. Therefore, intervention programs to prevent risky behavior of overweight and obesity in students is essential