A 46-year-old female was admitted to our hospital complaining of dizziness. Echocardiography and magnetic resonance imaging showed a pedicled tumor in the right ventricular outflow tract (RVOT), causing severe obstruction during systole. Resection was performed under cardiopulmonary bypass. Postoperative course was uneventful, with complete disappearance of major symptoms. Histological examination revealed the nature of the tumor to be a benign hemangioma. As reports of cardiac hemangioma causing severe RVOT obstruction are extremely rare, this case warrants attention.