UNLABELLED: 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.