Introduction. Obstruction is an acute condition of the abdominal cavity termed “acute abdomen”. This condition is managed surgically with an emergency procedure. Obstruction is not, however, a homogenous disease entity. Rather, it is a set of conditions causing similar symptoms. One of the reasons for developing obstruction may be cancer of the colon. Aim. The aim of this paper was to present a case of intestinal obstruction caused by a synchronous colorectal cancer. Materials and methods. This work presents a diagnostic procedure conducted in an Emergency Department and a surgical treatment carried out in the General Surgery Teaching Hospital concerning an 81-year old patient who reported symptoms of intestinal obstruction. Case study. A patient with typical symptoms of intestinal obstruction reported to the Emergency Department. He manifested: retention of gases and constipation lasting for a few days, abdominal distension, abdominal pain, and general weakness. Auscultatory examination detected high-pitched tinkles, X-ray of the abdominal cavity – the presence of multiple gas-fluid levels. Rectal examination revealed rectal tumor. Obstruction was diagnosed and hospitalization and surgical treatments were advised, to which the patient consented. On the day the patient was admitted, a Miles’ operation was performed. During a routine inspection of the abdominal cavity, a tumor in the hepatic flexure was also detected. It was decided to carry out a right hemicolectomy. No postsurgical complications occurred in the postoperative period. Parenteral nutrition was administered. The patient was discharged in a good general condition and advised to continue his therapy in the Outpatient Oncology Clinic, having received the result of the histopathological test. Results and discussion. The phenomenon of the co-occurrence of neoplasms in various organs has been known for quite some time. Often, neoplasms are located far away from each other, and sometimes two or more tumors are detected within the same organ. Synchronous neoplastic tumors within the colon are well documented, and their incidence is estimated by various authors to range from 1.02% to 12.4%. Conclusions. A synchronous cancer of the colon is so common that each neoplasm of this organ necessitates a thorough inspection of the entire intestine.