Objective To investigate the predictive value of Lp-PLA2 on the successful rate of thrombolysis in patients with a-cute myocardial infarction (AMI) .Methods Patients with AMI within 6 hours of onset were enrolled and blood samples before thrombolysis were drawn for laboratory examination .Alteplase was used for thrombolysis and 2 hours later ,successful rate and the predictive value of baseline Lp-PLA2 level on successful rate were evaluated .Results Totally 106 patients with AMI were enrolled and 48 cases were with anterior AMI ,32 cases with inferior AMI ,12 cases with lateral AMI ,and 14 cases with right ventricular and posterior AMI .Serum levels of cardiac biomarkers ,hs-CRP and Lp-PLA2 were all increased .Two hours later ,38 cases (35 .8% ) were with successful thrombolysis and 68 cases(64 .2% )were with failure ,and there were significant differences of baseline levels of hs-CRP and Lp-PLA2(P<0 .05) .hs-CRP was not correlated with successful rate of thrombolysis (r= -0 .17 ,P=0 .084) ,while Lp-PLA2 was negatively correlated with successful rate of thrombolysis(r= -0 .36 ,P=0 .013)as indicated by the Spearman rank correlation analysis .Conclusion Serum level of Lp-PLA2 can be used to predict the successful rate of thrombolysis in patients with AMI .