We reported a rare case of spontaneous frank rupture of a small (4 mm) penetrating aortic ulcer in the ascending aorta resulted in catastrophic bleeding. The ulcer only created a pinhole wound in the adventitia without saccular aneurysms, intramural hematomas, or aortic dissections. Notably, the wound could be directly closed because the aortic wall was intact only 5 mm away from the bleeding site. The postoperative course was uneventful, and the patient was discharged on the 11th postoperative day. After 8 months, follow-up computed tomography showed no abnormality of the aortic wall at the repair site.