Abstract： Objective:To explore the effect on patients with ST-segment elevation myocardial infarction (STEMI) undergoing intracoronary recombinant human prourokinase and tirofiban targeted therapy.Methods:This study was a randomized controlled trial study, a total of 90 patients with STEMI were selected from the department of Emergency in Xi ′an Central Hospital from January 2021 to March 2023, including 50 males and 40 females, aged (60.14±6.52) years old, ranging from 40 to 80 years old.The patients were randomized into tirofiban group and combined treatment group, with 45 cases in each group.Patients in the tirofiban group were injected with concentrated solution of tirofiban for injection at the proximal end of target diseased vessels, while the patients in the combined treatment group were injected with concentrated solution of tirofiban for injection combined with recombinant human urokinase for injection at the proximal end of target diseased vessels.The myocardial microcirculation perfusion, myocardial injury markers [creatine kinase isoenzyme (CK-MB), cardiac troponin l (cTnl), heart fatty acid binding protein (H-FABP)], cardiac function [left ventricular end-diastolic diameter (LVEDd), left ventricular mass index (LVMI), left ventricular ejection fraction (LVEF)], occurrence of bleeding events and occurrence of major adverse cardiovascular events (MACE) were compared between both groups.Results:The myocardial perfusion time constant k values of basal ring, middle ring and apical ring in basic state in combined treatment group (1.39±0.09, 1.41±0.10, 1.39±0.08) were higher than in tirofiban group(1.34±0.07, 1.36±0.08, 1.32±0.06), and the k values in load state (1.48±0.12, 1.51±0.11, 1.54±0.07) were higher than in tirofiban group(1.43±0.09, 1.44±0.08, 1.49±0.06).At 24 h after surgery, the levels of CK-MB, cTnl and H-FABP in combined treatment group[(88.53±18.89) U/L, (3.88±0.87) μg/L, (17.43±3.78) μg/L] were lower than those in tirofiban group [(101.25±20.55) U/L, (4.54±1.25) μg/L, (20.29±4.46) μg/L]; at 3 months after surgery, LVEDd and LVMI [(42.25±4.62) ml, (110.92±12.33) g/m 2] in combined treatment group were lower than (46.74±5.11) ml, (119.73±14.41) g/m 2] in tirofiban group, LVEF [(58.52±6.03)%] was higher than tirofiban group[(53.88±5.34)%], the differences were statistically significant ( P<0.05).The incidence of bleeding events and MACE were compared between the two groups, the differences were not statistically significant ( P>0.05). Conclusions:Intracoronary targeted combination of human prourokinase and tirofiban for STEMI patients can improve myocardial microcirculation perfusion, reduce myocardial injury, and help to restore cardiac function, and it has low incidence rate of postoperative MACE and good safety.