Spontaneous rupture of the aorta through an atherosclerotic lesion without preexisting aortic aneurysm, dissection, or history of trauma is very rare. Without prompt aortic repair, all cases result in sudden death with a definitive diagnosis made only intraoperatively or during autopsy. The phenomenon has been uniformly found in individuals with hypertension. The author reports a sudden unexpected death caused by spontaneous rupture of the ascending aorta in a 57‐year‐old man with a history of hypertension. The ascending aortic wall showed a longitudinal intimal tear measuring approximately 1 cm in length and rupture of the ascending aorta through an atherosclerotic ulcer, leading to massive hemopericardium and eventual death. Chronic hypertension and a penetrating atherosclerotic ulcer of the ascending aorta were the apparent underlying etiologies of the aortic rupture in the present case. This case illustrates not only the association between a rupture and a penetrating atherosclerotic ulcer with a silent death, but also raises awareness of possible such deaths.