Recent studies indicate that the prevalence of gastroesophageal reflux disease in Asia is either increasing or better recognized. There is a paucity of reliable data on the prevalence of reflux disease in the various races in general and in Malaysia, in particular. The prevalence of erosive esophagitis and Barrett's esophagus in a multiethnic Malaysian population was studied, as well as the relationship of various factors associated with reflux disease. Chinese, Malay, and Indian patients undergoing gastroscopy in a tertiary referral center were assessed for the presence of esophagitis, hiatus hernia, and Barrett's esophagus. Patient demographics and risk factors associated with gastroesophageal reflux disease were also documented. The prevalence of endoscopically documented esophagitis among 1985 patients was 6.1%, the majority of which were mild, Grade I or II (88%). There was a preponderance of Indians with esophagitis, as well as males (P < 0.05) and those with the presence of a hiatus hernia (P < 0.01). Long-segment Barrett's esophagus was found in 1.6% of patients, and short-segment Barrett's in 4.6%. Indians had the highest prevalence of Barrett's esophagus compared with Chinese (P < 0.05) or Malays (P < 0.01). Hiatus hernia and erosive esophagitis were both positively associated with Barrett's metaplasia (P < 0.01). A significant proportion of Malaysian patients undergoing endoscopy has mild reflux esophagitis and Barrett's esophagus. Indian ethnicity and the presence of a hiatus hernia were significantly associated with endoscopic esophagitis and Barrett's metaplasia. These observed racial differences warrant further study.