Objective To investigate the changes of coagulatory function in septic rats induced by cecal ligation and puncture (CLP). Methods Cecal ligation and puncture (CLP) were performed to induce sepsis in SD rats. Coagulation indexes were detected at 8, 16 and 48 h after operation, and histopathological changes of the lung, kidney, liver and spleen were examined using HE staining. Results The 12-day survival rate of the CLP-induced septic rats was 30%, with an acute onset and high mortality. In the acute phase of disease development of the CLP rats, the activated partial thromboplastin time (APTT) was prolonged ( P <0.05) at 8 h, the prothrombin time (PT) was prolonged at 16 h ( P <0.05), the factor XII activity in the endogenous coagulation pathway and the factor VII activity in the extrinsic coagulation pathway showed a transient inhibition, the thrombin time (TT) was prolonged at 48 h ( P < 0.01), and the content of fibrinogen (FIB) was increased gradually from 16 h ( P < 0.001). Among the other important coagulation and anticoagulation indexes, the number of platelets (PLT) was decreased gradually from 8 h ( P <0.01), while the number of vWF:Ag increased gradually from 8 h ( P <0.001). The D-dimer amount gradually increased from 16 h ( P <0.05), and the amount of PS:Ag significantly decreased until 48 h ( P < 0.001). However, there was no significant change in the antithrombin-III (AT-Ⅲ) content. The histopathological examination showed that there are different degrees of damages in the lung, kidney, liver and spleen tissues, but no obvious venous thrombosis and bleeding were found. Conclusions In the acute phase, there is coagulatory dysfunction in the septic rats, however, no histopathological changes such as venous thrombosis and bleeding were observed in the lung, kidney, liver and spleen tissues due to coagulatory dysfunction.