The 30-day mortality is one of the factors reflecting the quality of treatment. All these efforts focused on decreasing 30-day mortality will directly improve quality of care. The aim of the study was to identify risk factors of 30-day postoperative mortality in a cohort of patients operated on for colorectal cancer in one tertiary colorectal centre. Material and methods. Patients operated on due to colorectal cancer (CRC) between 2008 and 2014 were included in the study. 30-day mortality was assessed as an endpoint of the retrospective study. All records were collected from prospective database. Results. 1744 patients were operated on due to CRC. The 30-day mortality was noted in 65 patients (3.5%). In multivariable analyses we revealed that spread disease and poor general condition at admission were risk factors of 30-day mortality: OR 2.35; 2.01‑2.57 95%CI, p=0.03 and OR 2.18; 1.95‑2.41 95% CI; p=0.01, respectively. Emergency surgery significantly increased the risk of 30-day mortality: OR 2.64; 2.45‑2.87 95%CI; p=0.009. Low serum albumin concentration level and diabetes mellitus were additional risk factors for 30-day mortality, OR 1.65; 1.52‑1.78 95%CI; p=0.01 and OR 1.67; 1.41‑1.82 95%CI; p=0.03, respectively. Mortality was significantly higher after resection procedures than after only palliative operations: 4.21% vs 1.57%; p=0.002. Conclusions. Emergent patients, patients with advanced disease and in poor general state have to be assessed by multidisciplinary team to prepare them to operation. Additionally to reduce the risk of 30-day mortality decision of extend of surgery should be made by experienced surgeons.