Aim. To determine the value of ultrasound investigations, colonoscopy and laparoscopy in the complex diagnosis of acute obturative colonic obstruction of tumor genesis and in selecting the optimal treatment strategy. Methods. Conducted was an anlysis of results of treatment of 112 patients with obturative colonic obstruction of tumor genesis. A set of diagnostic procedures was carried out for every admitted patient: digital rectal examination, radiography of the abdomen, ultrasound examination, fiber colonoscopy, and laboratory studies. Results. Based on the clinical and radiographic the diagnosis of obturative colonic obstruction was established in 64.3%, ultrasound investigation revealed the presence of bowel obstruction without specifying its location in 92% of the cases. Emergency colonoscopy was informative only in 55.5% of cases due to inadequate prior preparation of the colon. Using the developed methodology of preparing the colon, it was possible to perform colonoscopy up to the level of the tumor in 26 patients (92.9%) out of 28 patients. In the 32 cases minimal surgical intervention were performed by way of formation of an ileotransverse anastomosis by-pass, double-barreled ileostomy or colostomy. 80 patients underwent resection of the bowel with the tumor, including operations with the formation of a primary anastomosis, which were performed in 20 patients when the tumor was located in the right segments of the colon. In 22 patients an intraoperative colonic lavage was performed. Postoperative complications were recorded in 30 (26.8%) patients. Postoperative mortality was 24.1% (27 patients). Conclusion. Based on the radiographic and ultrasound investigations of the abdominal cavity it is possible to establish the presence of bowel obstruction without specifying the localization of the obstruction zone; in order to determine the cause of the obturative colonic obstruction it is necessary to perform an emergency colonoscopy with rigorous preparation of the colon according to the developed technique, while the volume of surgical intervention should be determined in each case individually.