Objectives: To estimate obesity prevalence among children and adolescents in Al-Ahsa, Saudi Arabia for the year 2016 and to determine the related preventable risk factors. Methods:This study was a cross-sectional study (using stratified random sampling representing different geographical areas of Al-Ahsa) through a self-administered questionnaire. It included 240 male students aged (7-15) years old from public primary and intermediate schools in Al-Ahsa governorate, Kingdom of Saudi Arabia. Anthropometric measurements of weight and height were taken for all the study participants. Body mass index (BMI) and its percentile was determined using Saudi won growth charts of the corresponding age and sex. Results:The overall prevalence of overweight and obesity was 29.6% (10.8% overweight, 3.8% obese, and 15% extremely obese). The prevalence of overweight and obesity was significantly associated with early childhood obesity, parental obesity, mother's employment, family income, number of snacks and fast food consumption, physical inactivity, and time spent in watching television. Other factors (namely, eating during emotional stress, family gathering on meals, and regular eating times) were having independently significant association. Conclusion:There is an urgent need to spread awareness about obesity, and the prevention programs that involving schools and families are the key strategy for controlling the current epidemic of obesity.