Patients with chronic renal failure (CRF) have a high incidence of malignant tumours. Uremia thus induces a remarkable suppression of immune status. In this study, we report that within the last 20 years, 188 (6.7%) various organ tumours were found in 2817 CRF patients that were hospitalised and treated. 69 (36.7%) of 188 patients with various organ tumours were on hemodialysis and the rest (63.3%) were CRF without hemodialysis. 49 (71%) of the 69 patients with hemodialysis were diagnosed with tumours in the first year of the hemodialysis therapy. In 110 (84%) of 119 CRF patients tumours were detected in less than 10 years after diagnosis of CRF. Localisation of the tumours were: 39 (19%) urologic malignancy, 30 (16%) parathyroid adenoma, 28 (15%) skin malignancy, 19 (10%) gynaecologic malignancy, 18 (9.5%) gastrointestinal tract (GIT) malignancy, 17 (9%) lung malignancy, 17 (9%) larynx malignancy, 13 (7%) thyroid malignancy, 5 (2.6%) multiple myeloma and 5 (2.6%) malignant lymphoma. No patients in the series had received a transplant kidney or were therapeutically immunosuppressed for other reasons and obstructive uropathy. CRF patients have a several times greater risk of developing malignant tumour than the general population.