Objective To improve the knowledge of pulmonary artery sarcoma ( PAS) and early diagnosis.Methods The clinical data of 8 patients with PAS confirmed by biopsy from April 2001 to April 2012 in Beijing Anzhen Hospital were retrospectively analyzed. Results There were 5 males and 3 females, with mean age of 46. 75 ±11. 47 years [ range: 32-67 years] . The main clinical manifestations were chest tightness, shortness of breath, intermittent syncope, heart palpitations at exertion, etc. Laboratory examinations showed the patients with PAS have no obvious hypoxemia and most of them have normal D-dimer level. Echocardiography revealed pulmonary hypertension, right ventricular enlargement, and echo of massive lumps in main pulmonary truck. Lower limb veins were normal in color doppler ultrasonography. Chest X-ray revealed prominent pulmonary artery segment, full segment of the right pulmonary artery, an increased hilum and pleural effusion. CT pulmonary angiography showed expansion of pulmonary artery, large filling defect in main pulmonary truck and left or right pulmonary artery, combined with pericardial effusion, pleural effusion. Lung ventilation/perfusion imaging did not match, showing radioactive sparse and defects in multiple lung segments and subsegments, involved 3 to 13 lung segments. Pulmonary angiography showed filling defects in the main pulmonary artery, left or right pulmonary artery. 8 patients were confirmed pathologically after operation. Pathological results showed leiomyosarcoma differentiation in 3 cases, undifferentiated sarcoma in2 cases, and undefined pathological type in 3 cases. All 8 patients were misdiagnosed as pulmonary embolism before surgery. The average days of misdiagnosis were 85. 6 ±21. 5 days. 7 cases were given simple surgical resection, one case underwent surgical resection combined with radiotherapy and chemotherapy. 7 cases were relieved and discharged, and one case died. Conclusion PAS is a rare disease clinically and is easily misdiagnosed as pulmonary embolism. Clinicians should enhance the recognition in order to diagnose early and treat comprehensively.