The aim of this study is to assess the morbidity and mortality related to cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) in patients with colo-rectal carcinomatosis. A retrospective multi-institutional study from seven Italian Centers was performed. One hundred and seventy-two patients, submitted to cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) to treat carcinomatosis of colorectal origin, were recorded. Postoperative morbidity was evaluated in accordance with the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) v4.03. Post-operative mortality was evaluated as patients' death within 60 days from surgical procedures. Predictors of morbidity were evaluated with univariate and multivariate analyses. Post-operative morbidity occurred in 83 patients (48.3%): grades 1-2 in 29 cases (16.9%), and grades 3-4 in 54 (31.4%). Mortality occurred in four cases (2.3%). Number of anastomoses (OR 1.45; 95% CI 1.05-2.00; p = 0.024), number of blood transfusions (OR 1.31; 95% CI 1.11-1.54; p = 0.001) and chemotherapy regimen [Oxaliplatin (OX): OR 2.87; 95% CI 1.22-6.75; p = 0.015] remained, in multivariate analysis, in a statistically significant correlation with overall morbidity. The only variable that was proven to have statistically significant correlation with 3-4 morbidity was the number of blood transfusions (OR 1.25; 95% CI 1.07-1.46; p = 0.005). Morbidity and mortality do not preclude the use of CRS plus HIPEC in the treatment of peritoneal carcinomatosis of colorectal origin.