A review of 238 patients aged over 75 years and operated on for colorectal cancer was undertaken to analyse factors influencing short and long-term operative mortality. Operative mortality in the first postoperative month was 13% (n = 31) and 17% (n = 35) in the first year. Four factors influenced significantly postoperative mortality in the first month: postoperative complications (p = 0.0001) related to medical complications (p = 0.0001), emergency surgery (p = 0.007), type of anesthesia (p = 0.01). Mortality during the first year (excluding patients who died in the first month) was higher in females (p = 0.05), in patients subjected to emergency operation (p = 0.004), in patients with preexisting, cerebrovascular accident (p = 0.04) and in patients with Dukes C staging (p = 0.0001). A multivariate analysis with Cox's model revealed 3 prognostic factors: Dukes staging (p = 0.0001), medical complications in the postoperative period (p = 0.0001) and type of anesthesia (p = 0.0009). Age as an isolated factor is not a contraindication to colorectal surgery in elderly patients presenting colonic or rectal carcinoma. Prognosis in elderly patients is first correlated to the control of postoperative mortality undergoing until the first year and then to the cancer itself.