Forty infants with suspected gastroesophageal reflux (GOR) underwent continuous 24 hour esophageal pH-metry and sonography of the gastroesophageal junction. In 29 out of 40 cases (72.5%) GOR was confirmed by the 24 hour pH-monitoring, because of a percentage of total time of reflux of 10% or more. The positive and negative predictive value of sonography versus the result of continuous 24 hour pH-monitoring was 80% and 50% respectively. Sonography cannot be considered a faithful diagnostic tool in screening for GOR in infants.