Gastropleural fistula is a relatively rare complication that can be seen as a result of traumatic, nontraumatic, benign, and neoplastic etiologies. Most commonly, these are found in patients with diaphragmatic herniation or prior thoracic surgery. Aortoenteric fistulas are rare communications typically between the abdominal aorta and bowel. We present a rare case of an 88-year-old male who developed a gastropleural fistula with erosions into the wall of the descending thoracic aorta. Computed tomography (CT) is a leading modality in evaluation of suspected gastropleural or aortoenteric fistulas given the quick scan time and widespread availability. Prompt diagnosis is essential and requires an understanding of appropriate CT protocols and CT imaging appearance.