The authors of the present paper outline the results of studying the use of routine transabdominal sonography and ultrasound irrigoscopy (UI) in the diagnosis of acute colonic obstruction (ACO) in 70 patients. The cause of ACO was tumor-induced colonic luminal obturation in 55 patients and colonic evacuatory dysfunction due to congenital anomalies and acquired constrictions of inflammatory genesis in 15 cases. UI was used to determine the presence, degree, and causes of colonic obstruction. The paper details the UI procedure developed by the authors and the ultrasound semiotics of ACO, shown by routine transabdominal sonography and UI. Analysis of the results of the studies allows the authors to state that UI is as highly informative as X-ray irrigoscopy in the diagnosis of ACO and may be included into a diagnostic algorithm in these patients.