Objective To study the thrombolysis effect and safety of UK combined with tirofiban in young patients with ST segement elevation acute myocardial infarction.Methods 76 young patients with ST segement elva-tion acute myocardial infarction were selected as research objects,and they were divided into UK group(control group, n =34)and UK combined with tirofiban group(observation group,n =42)by random number table,then the recanali-zation rate of infarct -related artery and incidence of complications were compared.Results The recanalization rate of infarct -related artery in the observation group was 97.6%,which was 91.2% in the control group,there was no significant difference between the two groups(χ2 =1.564,P >0.05);The vascular infarction related to blood flowⅡlevel of the patients was 90.5% in the observation group,which was significantly higher than 70.6% in the control group(χ2 =4.945,P <0.05);The death,complications incidences had not significant differences between the two groups(χ2 =1.252,2.837,2.837,all P >0.05).Conclusion The thrombolysis effect of UK has a high recanaliza-tion rate of infarct -related artery in young patients with ST segement elevation acute myocardial infarction,and the thrombolysis effect of UK combined with tirofiban is better,and it does not increase the incidence of complications.