Objective To determine the levels of soluble thrombomodulin(sTM) in patients with acute pulmonary embolism (PE), and evaluate sTM clinical significance.Methods The sTM levels were determined with enzyme linked immunosorbent assay in PE patients, and compared with healthy control group. Eighteen PE patients were divided into massive PE group and non - massive PE group, non - respiratory failure group and respiratory failure group, and compared the sTM level in the groups. Results Level of sTM in PE patients was higher than that of control group (P