Obstructive myxoma of the right ventricular outflow tract occurs rarely. A 22-year-old woman presented with a 3-month history of shortness of breath during exertion. Transthoracic echocardiography showed a huge mass in a dilated right ventricle. The mass, which obstructed the right ventricular outflow tract, was attached to the interventricular septum and protruded through the pulmonic valve during systole. The peak and mean systolic pressure gradients across the pulmonic valve were 79.9 and 47.8 mmHg, respectively. At surgery, the origin of the mass was attached to the right ventricular apex on its septal surface. The histopathological findings were characteristic of myxoma. The patient recovered uneventfully.