The aim of the study was to estimate factors affecting results of surgical treatment of colorectal cancer in octogenarian patients in comparison with a group of younger patients.Material and methods. Hospital records were reviewed prospectively and data were collected from a consecutive series of 1021 patients operated on because of primary colorectal cancer between 1988 and 2009.Results. One hundred sixteen patients aged minimum 80 years of life were identified with an average age of 83.6 years. They were compared with 905 younger patients with an average age of 61.9 years. Co-morbidity, presentation in ASA 2, ASA 3 and ASA 4 score were significantly higher in octogenarian than in younger patients group. Emergent operations were performed significantly more often in octogenerians than in younger patients as well (31% versus 14% respectively). Resection of cancer and primary bowel anastomosis was performed less often in patients aged over 80 years than in younger patients (58.6% versus 70.9% respectively). Postoperative complications rate was significantly higher among the older than younger patients (43.9% versus 30.7% respectively). Mortality was higher in older than in younger patients (22.4% vs 5.7% respectively).Conclusions. Results of surgical treatment of colorectal cancer in octogenarian patients are affected by higher co-morbidity and more often presentation of ASA 3 and ASA 4 score than in younger patients. Surgical treatment of colorectal cancer in octogenarians is burdened with higher rate of postoperative complications and almost four times higher mortality rate than in younger patients.