The commonest pathological findings in the upper gastrointestinal tract have been verified by studying 320 autopsies as related to chronic renal failure through the 20-year span. In our series of 99 patients having been hospitalized within the period of 1989 to 1990, lesions of upper gastrointestinal tract were summarized that might be responsible for bleeding in the course of the dialysis and after renal transplantation. In accordance with literature sources, the investigated group showed gastric and duodenal mucosal lesions to be the most frequent sources of hemorrhages. For both the early diagnosis and therapy all patients have to be examined prior to the initiation of a regular maintenance dialysis. Gastroscopy is also indicated in all patients without any exception. Subsequent conservative treatment should be performed in an intensive and accurate way. While unsuccessful, the surgery is indicated. Authors referred to indicatory criteria based on surgical management of gastroduodenal ulcer. Both the early diagnosis and indication to surgery were stated to be of crucial importance for patient's destiny when the conservative treatment has failed. The present study should contribute to a closer collaboration of nephrologists, gastroenterologists and surgeons in order to prevent such serious complications that are represented by gastrointestinal bleeding in patients with chronic renal failure.