Obesity is a serious epidemic that is increasing rapidly worldwide. Obesity in the UAE is associated with the rapid increase of wealth and the dramatic impact of economic development since the oil boom in the 1930s. The aim of the study is to determine the childhood obesity rates in Al-Ain City by comparing the CDC 2000 and IOTF BMI cut offs with various factors associated with overweight and obesity among children and adolescents. Data were obtained from 10 schools in Al-Ain for both male and female students ages from 8 to 16 years. The prevalence of overweight and obesity using CDC were 12% boys; 12.7% girls and 14% boys; 13.6% girls, respectively. Using the IOTF, 14.5% boys and 17.6% girls were overweight and 9.6% in boys and 12.9% girls were obese. Overweight and obesity are prevalent in Al-Ain City. Underweight seems to be another public health concern among schoolchildren.