Background: The new challenge for developing countries like Vietnam is to continue to address the underweight problem, while tackling the rising prevalence of overweight in urban areas. Objectives: Determine the prevalence and determinants of BMI among Vietnamese children ages 8 to 10 years in district 5 in HCMC and Cai Lay District in Tien Giang Province, using an international reference standard. Method: This investigation was based on direct interviews that included a socioeconomic, physical activity and body anthropometry was measured.