One hundred and fifteen patients with upper gastrointestinal bleeding diagnosed, between august 1992 and july 1995, at the "Victor Ramos Guardia" General Hospital in Huaraz (3,100 m.o.s.l.), Ancash, Perú, are here studied to know about epidemiologics and clinical aspects of this condition at high altitude. In all, the patients on upper endoscopy were done and gastric biopsy when it was required. The incidence of upper gastrointestinal bleeding for the population at risk was 9.6/ 10,000 in habitants by year, and the institutional prevalence was 12.3/1,000 hospital discharges. All the patients were native from the sierra of Ancash, 55.7% males, 37.4% older than 60 years at age; mean age 52.2 years (18 = 86), 50.4% admitted ingestion of gastroerosives, 55.7% presented with hematemesis and melena, 34.4% only melena, 41.7% had hemoglobin less than 8g/dl and 66.3% required or blood transfusion. The most frequent causes of upper gastrointestinal bleeding were gastric ulcer (29.6%), gastric cancer (26.1%), duodenal ulcer (17.4%), erosions (6.1%). No cause was detected in 7%. The endoscopy diagnostic certainty was 93%. 84.3% required medical treatment, 15.7% required surgical treatment and the global mortality was 4.3%. Attention is made on the high frequency of gastric ulcer and gastric carcinoma as the source of upper gastro intestinal bleeding, in the Indian population.