Five cases of duplication of the digestive tract are reported: oesophagus, stomach, duodenum, and colon. These patients were adults, in whom it is rare (5% of cases) to find such duplications. Two types of image are seen on barium meal examination: opacification of a lumen which may be abnormally blind and which can be easily diagnosed if it is short, but is sometimes more difficult to individualize if the duplication is long (colon); or an extrinsic type of compression which is a part of the wall and much more difficult to diagnose. Knowledge of these different types of radiological images in adults should avoid precipitous investigations and orientate possible surgical interventions.