The incidence rate of pulmonary artery sarcoma is very low, but its prognosis is extremely poor. In this case report, after various initial diagnoses at the early stage, pulmonary artery sarcoma was confirmed by surgery. 1 year later, the tumor recurred. After chemotherapy, the patient showed improvement of the subjective complaint of tightness in the chest, and radiological lesion decreased in size. The survival time was extended by 2.5 years. This is the first case report of pulmonary artery sarcoma with such chemo-sensitivity.