Background: High serum uric acid (UA) levels appear to contribute to an increase in blood pressure (BP) in obese adolescents and may amplify the cardiac volume overload effects of obesity with pressure overload. Association between UA and ejection fraction (EF) is still controversial. Some studies showed negatively correlations, others did not found any correlation. So far, no data have been published regarding the influence of UA levels on structural and functional changes of the LV in children with obesity. Objective: The aim of our study was to assess the influence of UA levels on LV structure and function in overweight/obese children. Study groups and methods: In 25 (mean age 13.0 ± 2.3) overweight/obese subjects and 24 lean controls, BP, fasting plasma glucose, insulin, and UA were measured. LV structural and functional parameters were measured by echocardiography. Results: In overweight/obese children UA correlates with LV diastolic volumes and LV systolic function but not with LVM whereas in children without obesity UA correlates with LVM and LV diastolic function. Conclusion: The present study demonstrates a positive correlation of UA with EF and left atrium and LV volume in volume overload due to obesity in children. These conclusions require further investigation.