Objective To observe the effect of reteplase on the thromboelastogram tracing of patients experiencing acute is-chemic stroke(AIS).Methods Selected 43 AIS inpatients in the Third People’s Hospital of Liaocheng from October,2013 to August,2015,who received reteplase less than 4.5 hours after the onset of syndrome of AIS.Blood samples were obtained before reteplase administration and at 0.5,1,2 and 4 hours after reteplase administration and measured by thromboelastogra-phy.Results The parameters R,K,Angle and MA of the thromboelastogram had changed after beginning administration of reteplase.The R value at 0.5 h after thrombolysis was significantly higher than that before thrombliysis,however,the R Value at 1h after thrombolysis was the most highest,and the K value.At 0.5 h after thrombolysis was the highest.At 0.5 h after thrombolysis MA and Angle values were the lowest,the differences were statistically significant (P<0.001).Conclu-sion The study suggests that the thromboelastogram is an useful tool for determining changes in the coagulation system of patients receiving reteplase.