Pulmonary artery rhabdomyosarcomas are rare lesions, with a small number of cases reported in the literature. We report a case of pulmonary artery rhabdomyosarcoma that arose in the right pulmonary artery. The patient presented with cough, chest pain, and hemoptysis and was found to have a sarcoma arising in the right pulmonary artery and extending distally within the pulmonary vasculature into the right lung. The gross pathologic features, microscopic appearance, immunohistochemical profile, and computed tomographic and electron microscopic findings are presented. The site of origin and differential diagnosis of these lesions are discussed.