Incomplete common mesentery (ICM) is a rotation anomaly of the primary intestinal loop. Its symptoms are nonspecific, ranging from repeated abdominal pain with transit disorders to extremely serious occlusive complications that are life-threatening. It is a rare pathology in adults, which can lead to diagnostic wandering. It is important to know the radiological signs, especially CT scans, for early treatment. We report the observation of a 57-year-old patient received for mechanical occlusion of the proximal small intestine on an incomplete common mesentery diagnosed on abdominal computed tomography (CT) and confirmed by surgical exploration, in whom the evolution was favorable.