Epstein-Barr virus-associated smooth muscle tumor (EBV-SMT) is an exceedingly rare neoplastic disease with a predisposition in immune-compromised individuals, especially in patients with prior transplantation, human immunodeficiency virus infection, or congenital immunodeficiency. Here, we present imaging findings of EBV-SMT in multiphasic contrast-enhanced computed tomography (CT) and fluorine-18-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/CT in a two-and-a-half-year-old boy with prior heart transplantation.