Three cases of traumatic intrapericardial diaphragmatic hernia are reported. The defect was limited to the central tendon of the diaphragm in all 3 cases with herniation of the transverse colon (n = 2) or small bowel (n = 1) into the pericardial sac. A correct preoperative diagnosis was made in all 3, using a dilute barium meal in 2 patients, and from the chest X-ray examination alone in 1. Successful operative repair was performed. Previous reports suggest that barium studies of the gastrointestinal tract are the most accurate method of diagnosis but should be used with caution as they may precipitate cardiac tamponade through distension of herniated bowel.