Introduction and aim. Assessment of risk of complications in umbilical hernia is important. The aim of this study was to evaluate the effect of size of the umbilical ring on the risk of complication occurring in umbilical hernia. Material and methods. This was a prospective study of children who had umbilical hernia repair for symptomatic umbilical hernia. Using Vernier caliper, the umbilical ring diameter (URD) was measured at surgery and the patients were divided into 2 groups. Group A had URD of less than of 15 millimeter (mm) and group B patients had URD of 15 mm and above. The 2 groups were compared. Results. Thirty two cases were evaluated. Their mean age was 42 months. All the patients had umbilical pain. Twenty six (81.3%) patients had URD of less than 15 mm (group A) whereas 6 (18.7%) patients had URD of greater or equal to 15 mm (group B). Group A patients had a mean URD of 12.1±3.4 mm whereas group B patients had a mean URD of 30.5±5.0 mm (p=0.001). Conclusion. Children who have URD of less than 15 mm are at a higher risk of developing umbilical hernia complications.