A retrospective review of 35 patients with diaphragmatic injury attended at the Emergency Service of the Hospital das Clínicas, University São Paulo is analysed. Diagnosis was made through chest roentgenogram (48.5%), peritoneal lavage (37%) and contrast studies (14.5%). The most common extra-abdominal lesion were due to head, pelvic and thoracic trauma. Thirty-one patients sustained injuries to the left-side and four to the right. Associated intra-abdominal injury occurred in 89% of them. Retroperitoneal haematoma, spleen and liver injury were the most frequent lesions. All cases were treated by laparotomy, pleural space irrigation through the diaphragmatic lesion, thoracic drainage and suture of the injury. The morbidity rate was 40% and deaths occurred in 22.8%. Based upon these data, we concluded: the mechanism of trauma, chest RX findings and pelvic fracture are important clues for early recognition; irrigation of pleural space seems to be important in order to prevent empyema. Despite of this, the mortality remains high.