The aim of the study was to determine the prevalence of overweight and obesity in children in the United Arab Emirates (UAE). Secondary analysis was undertaken of data on 4381 children aged 5–17 years from the 1999 UAE-National Iodine Deficiency Surveillance Study. Data on weight and height from that study were used to calculate body mass index. The prevalence of overweight and obesity was estimated using International Obesity Task Force criteria. Overall, 944 (21.5%) of children were overweight and 601 (13.7%) of these were obese. More girls than boys were overweight (22.9% vs. 20.2%; P ≤ 0.001). Non-citizen girls were more likely to be obese (odds ratios [OR] 1.767, 95% confidence intervals [CI] 1.48–2.102) than UAE girls. Boys in the rural areas had the lowest prevalence (23.6%) and were the least likely of all the children to be either overweight (OR 0.785, 95% CI 0.629–0.974) or obese 0.732 (95% CI 0.591–0.912). This study demonstrates a high prevalence of overweight in children in the UAE. Prompt actions are needed to initiate preventative and interventionist strategies to reverse the trend of this emerging epidemic.