Abstract: Objective: To investigate the predict value of the mean platelet volume(MPV) on prognosis of the ischemic stroke patients treated with recombinant tissue type plasminogen activator(rtPA) intravenous thrombolysis.Methods: The prognosis of patients treated with rtPA thrombolysis was evaluated using the modified Rankin scale(MRS).The patients were divided into the good prognosis group and poor prognosis group,and the influence of MPV on the prognosis of patients treated with rtPA thrombolysis was discussed.Results: The differences of the age,incidence rate of atrial fibrillation,aspirin use history,systolic blood pressure,diastolic blood pressure,NIHSS score,INR,blood glucose,total cholesterol,high-density lipoprotein cholesterol,low density lipoprotein cholesterol,thrombocytocrit,MPV,platelet distribution width and CISS typing between two groups were statistically significant(P<0.05 to P<0.01).Logistic regression analysis showed that the age,previous aspirin use history,baseline NIHSS score,blood glucose,LDL-C,MPV,PDW,cardiogenic stroke and perforating artery disease were the independent influencing factors of the prognosis of rtPA thrombolytic therapy(P<0.05 to P<0.01).Linear regression analysis showed that the MPV was negatively correlated with MRS score(P<0.05).The best clinic point of MPV in the diagnosis of the prognosis of rtPA thrombolytic therapy was 10.12 fL,and the sensitivity,specificity,AUC,negative predictive value,positive predictive value and accuracy of MPV were 89.2%,87.8%,0.882,84.6%,91.5% and 88.4%,respectively.Conclusions: MPV has a certain predictive value in rtPA thrombolysis treating acute ischemic stroke,which is an independent risk factor of short-term thrombolysis treatment.