Background: Childhood obesity is a worldwide epidemic, with prevalence rates doubling or tripling over the past 15 years. Childhood obesity is due to the imbalance between caloric intake of the child and the calories utilized (for growth, development, metabolism, and physical activities). Obesity negatively affects the child's quality of life (QOL) specifically the dimensions that related to psychosocial health, self-esteem, physical functioning, and the impact on parental emotional well-being. Aim of the study: to Assess quality of life among obese preadolescent school age children (11-14 years) at Minia City. Research design: A descriptive research design was utilized in the present study. Setting: Four preparatory schools were chosen randomly. Two private schools one from south and other from north of Minia city. Similarly, two governmental were chosen, one from the north and other from the south, including both private schools (Mosaab Ben Omaier), and (Salah El-Dien Islamic school) and governmental schools (El- Salam preparatory, and El- Etehad preparatory school). Subjects: A random sample of 100 students. Tool of data collection: Tool 1: A structured interview questionnaire. Tool 2: The Pediatric Quality of Life Inventory (PedQL). Tool 3: anthropometric measurements: Weight, Height, and body mass index. Results: Mean age (13.11± 0.86) their weight ranged from (71-136 kg) with mean weight was (88.2± 10.7kg) & the height ranged from (1.41-1.7 m) and mean height was 1.56±0.061 and their BMI ranged from (31.2-50.4) and the mean of BMI was 35.7±3.6. There are strong correlation between BMI and QoL and this correlation was statistically significant (r=0.23, p=0.01).Conclusion: It was concluded that Obesity has a negative impact on the children's daily life. Obese children reported poorer quality of life as regards the physical, emotional, social, school functioning domains and total quality of life. Recommendations: Strategies should be directed toward improving the quality of life of overweight and obese adolescents. We are in need to increase public awareness and information about healthy balanced diet, nutritional needs, and practicing adequate physical activities in all age groups especially school age through mass media. School nutritional health education programs must be organized to encourage healthy eating habits as a routine part of healthy life for all, with a combination of exercises on a daily basis.