The records of 2,982 patients who were subjected to upper gastrointestinal (UGI) endoscopy were retrospectively analyzed. All patients were seen at King Fahd Hospital of the University, Al-Khobar during the period 1982-1986. All were adult patients with a mean age of 46 years, of whom two thousand nine (67.4%) were males. The commonest endoscopic diagnosis was chronic gastritis (21.4%) followed by duodenal ulcer (17%) and chronic oesophagitis (11.7%). Of 1,256 biopsied patients a 'histologically normal' diagnosis was obtained in 565 (45%) from all sites. However, chronic non-specific superficial gastritis (22.6%) followed by chronic duodenitis (17.5%) constituted the two commonest histological diagnoses. Helicobacter pylori was identified histologically on the gastric mucosa of 72% of patients with superficial chronic active gastritis, with or without associated peptic ulcer disease. Duodenal ulcers followed by oesophageal varices were the two commonest diagnoses encountered in 200 patients presenting with UGI bleeding. These results are discussed and compared to those of other studies.