Spontaneous coronary artery dissection is a very rare event and occurs most often in young women following childbirth. It is also known as a rare focal complication in Churg-Strauss syndrome. Here, we present the case of a 43-year-old woman who died after spontaneous dissection of all three coronary arteries. The microscopic examination of coronary vessels showed severe eosinophilic infiltrations, whereas all extracardiac (medium-vessel and large-vessel) arteries were intact and free of inflammatory cells. Her history did not reveal allergy, asthma, or eosinophilia. To the best of our knowledge, this is the first case of spontaneous coronary dissection involving all coronary arteries without a history of Churg-Strauss syndrome or hypereosinophilic syndrome.