Giant coronary artery aneurysms are relatively rare and are usually associated with Kawasaki disease, atherosclerosis, congenital disease, or trauma. Although a coronary-pulmonary artery fistula is a known complication, clear guidelines for treatment of this condition remain unavailable. We report a case of multiple giant coronary artery aneurysms associated with a coronary-pulmonary artery fistula in a patient who underwent fistulotomy, aneurysmectomy, and coronary artery bypass graft surgery. A 66-year-old woman was initially evaluated by her primary care physician following right breast cancer surgery. She denied any specific symptoms; however, she was referred to our hospital for evaluation of an abnormal shadow detected on chest radiography. Contrast-enhanced computed tomography (CT) performed at our hospital revealed multiple giant coronary artery aneurysms(approximately 45 mm in size), as well as right and left coronary-pulmonary artery fistulas. We performed simultaneous aneurysmectomy, fistula resection, and coronary artery bypass grafting for management of the giant coronary artery aneurysms concomitant with coronary-pulmonary artery fistulas. Threedimensional CT was useful for accurate imaging of the location of the coronary artery aneurysms, fistula vessels, and the left anterior descending, and left circumflex arteries. It is essential to accurately delineate the boundary between the aneurysms and healthy coronary arteries and fistula vessels, and coronary artery bypass graft surgery should be performed if necessary. We report a rare case of the aforementioned clinical condition, together with a literature review.