Introduction: Childhood obesity is a serious medical condition that affects children and adolescents. Children who are obese are above the normal weight for their age and height. The frequency of obesity has been differed potentially from country to country according to the socio-demographic levels. In reducing the increasing incidence of childhood obesity environmental approaches and population-based social strategies should be considered as effective initiatives. Aim of the study: The aim of this study was to assess the characteristics of school going obese children of Dhaka metropolitan city. Methods: This was a cross sectional study which was conducted in the Department of Pediatrics, Sir Salimullah Medical College & Mitford Hospital, Dhaka and some metropolitan school in Dhaka city, Bangladesh during 1 June 2009 to 28 February 2010 (9 months) on school going obese children (age 6 years to 18 years) of Dhaka metropolitan city. Sample size was 110 (one hundred and ten) and schools were selected first by purposive sampling and then students were selected by random sampling. Data were entered, coded, cleaned, and analyzed by using Statistical Package for Social Science (IBM SPSS), version 12. Results: In analyzing the socio-demographic risk factors we found, among the participants 18(16.4%) were girls and 92(83.6%) were boys. 78.2% students lived with both parents (father and mother) and 21.8% students lived only with mother. Fifty percent parents have parents have education above graduation, 40% were Graduate, 6.4% has college education and 3.6% has secondary education. More than half of the families (56.4%) has income>20000/- and 43.6% income 10000-20000/. Conclusion: In our study we found gender and food habit of the participants as the most potential factors for child obesity. The findings of this study may be helpful for the physicians in treating obese children and in further related studies.