Introduction: Congenital diaphragmatic hernias are extremely rare in adults. Small congenital defects are usually asymptomatic and may remain undiagnosed until adulthood. Progressive herniation may cause bowel obstruction and subsequent infarction. Methods: We present a case of a 54-year-old male who was diagnosed with a large left diaphragmatic hernia after aspiration pneumonia. Results: Upon trocars placement and laparoscopic exploration, a very large defect was evident in the posterolateral left diaphragm. The hernia sac content included the stomach, colon, spleen and omentum. After lysis of posterolateral adhesions, the herniated contents were reduced into the abdominal cavity. The diaphragm defect was weak anteriorly with minimal edge of muscle present. Therefore, the decision was to perform a small incision in the hernia sac followed by its plication. A 25x20cm polypropylene mesh was then placed and fixated using barbed sutures against the edges of the diaphragmatic defect. The patient tolerated the procedure well and was discharged on postoperative day 5. Conclusion: Congenital diaphragmatic hernias are uncommon in adults, but present a potential risk of complication. Surgical management is the ideal treatment, except for those who do not qualify for surgery.