Objective To analyze spiral CT manifestations and the diagnostic value of pulmonary embolism (PE).Methods Spiral CT pulmonary angiography (SCTPA) and chest plain CT scan were performed in 25 cases with highly-suspected PE. CT findings were retrospectively analyzed.Results The direct signs of PE appeared as complete or partial filling defect within pulmonary arteriae on SCTPA.191 branches of pulmonary artery were involved in all cases,of them, 44 branches were centrally located(23.0%), 115 branches were eccentrically located (60.2%),7 branches were mural filling defect (3.7%), 25 branches were complete occlusion (13.1%).The indirect signs of PE included irregular consolidation (n=15), patchy ground glass opacities (n=6),local streak shadows(n=4),"mosaic"sign (n=5), pleural effusion(n=16) ,pericardial effusion (n=3)and simple emboli no other signs(n=3).Conclusion SCTPA is a fast ,effective, security and non-invasive diagnostic method for PE .