An epidemiological survey about the incidence of upper gastrointestinal bleeding during three periods (1980, 1985 and 1990), was performed in 9 Chilean hospitals. Its annual incidence decreased in 1990, when compared to 1980. Likewise the etiologies changed, with an increase in the incidence of duodenal ulcers and a decrease in the incidence of erosive gastritis and bleeding of unknown origin in 1990. A seasonal variation with higher bleeding rates in autumn was also recorded.