Rationale: We present a case of appendicitis with an uncommon course due to rare anatomical location of the appendix in the right retroperitoneal space below the diaphragm and above the liver.Patient's concern: A 32-year-old, previously healthy male with a history of congenital diaphragmatic hernia repair in childhood, presented with 3 days of mild, colicky, central abdominal pain associated with fever, nausea and vomiting. At presentation, pain was localized to the right lower quadrant. Diagnosis: Even though diagnosis of appendicitis was clear, we decided to confirm it with computer tomography (CT). CT revealed elevation of the right dome of the diaphragm and perforated appendix located above the liver. Intervention: Appendectomy was performed via right subcostal approach instead of usual incision in the right lower quadrant. Outcome: Patient recovered well and was discharged on the 5th day after operation. Lessons: Previous congenital diaphragmatic hermia repair may change the location of the appendix. The appendix at rare locations could lead to an uncommon course of appendicitis. On this very note, surgeons should have a high index of suspicion, and CT may help avoid inadvertent complications.