Pathological gastroesophageal reflux, prolonged gastric emptying and abnormal gastric potential difference have been claimed to be functional disorders often detectable in non-ulcer dyspspsia (NUD). The role of Helicobacter pylori in NUD is still unclear. The aim of the present study was to evaluate the prevalence of these factors in 47 patients with NUD. According to DeMeester's criteria, 60 percent of NUD patients had abnormal gastroesophageal reflux, while 38 percent had prolonged gastric emptying of a liquid meal. Seventy-nine percent showed abnormal gastric potential difference which was unrelated to Helicobacter pylori colonization, detected in 46 percent of NUD patients. When esophageal pHmetry, gastric emptying evaluation and measurement of gastric potential difference were performed, 89 percent of NUD patients presented at least one abnormal finding.