Background: Advanced age is a risk factor for colorectal cancer, and very elderly patients often need to be surgically treated. This study aimed to analyze the outcomes of a cohort of nonagenarian patients operated on for colorectal cancer. Methods: Observational study conducted on a cohort of 40 nonagenarian patients, who were treated surgically for colorectal cancer between 2000 and 2018 in our institution. Clinical data, ASA score, Charlson Comorbidity Index, Surgical Mortality Probability Model, tumor characteristics, and nature and technical features of the surgical procedure, were recorded. The Comprehensive Complication Index (CCI) and survival time after the procedure were recorded as outcome variables. Univariate and multivariate analyses were performed in order to define risk factors for postoperative complications and long-term survival. Results: Out of the 40 patients, 13 (32.5%) were men, 27 (67.5%) women, and mean age 91.6 years (SD ± 1.5). In 24 patients (60%), surgery was elective, and in 16 patients (40%), surgery was emergent. Curative surgery with intestinal resection was performed in 34 patients (85%). In 22 patients (55%), intestinal continuity was restored by performing an anastomosis. The median CCI was 22.6 (IRQ 0.0-42.6). Operative mortality was 10% (4 patients). Cumulative survival at 1, 3, and 5 years was 70%, 47%, and 29%, respectively. In multivariate analysis, only the need for transfusion remained as an independent prognostic factor for complications (p = 0.021) and TNM tumor stage as a significant predictor of survival (HR 3.0, CI95% 1.3-7.2). Conclusions: Colorectal cancer surgery is relatively safe in selected nonagenarian patients and may achieve longterm survival.