METHODS: A retrospective analysis of the results of pre-operative use of rifaximin was performed in 181 patients scheduled for rectal and colorectal cancer between 2013 and 2016 in the General Surgery Unit with the Orthopedic and Urology in the Hospital of the Ministry of Interior and Administration in Lublin. Patients undergoing urgent surgery were excluded from the study. Patients were divided into 2 groups. The first group of 139 patients - patients operated on for rectal and colorectal cancer in 2013 until 2015, in whom rifaximine was not used in the preoperative period. The second group is 42 patients, operated on in 2016, in which the rifaximin was used in the pre-operative period at a dose of 2x2 tablets (400 mg) per day, 12-hour interval, for 7 days before the planned operation. Additionally, a probiotic was administered for 7 days. Drugs were ordained at the Oncological Outpatient Clinic as part of the pre-hospitalization check. R esults: The use of rifaximin in the preoperative period in patients with colorectal cancer had an effect on shortening the time of post-operative hospitalization and reduced post-surgical pain in comparison with the control group. The analysis of the cynumber and intensity of surgical complications in both groups did not differ. C onclusions: Large studies on the influence of rifaximin on the development of colorectal cancer have not been published so far. Only single reports suggest that its use has a positive effect on the perioperative period of patients treated for colorectal cancer including rectum and our retrospective analysis confirms these observations.