Abstract: AIM To investigate the effect of shuxuetong injection on patients with acute ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). METHODS Eighty STEMI patients who were to receive primary PCI were randomly assigned to shuxuetong injection group (n=40) and tirofiban group (n=40). Baseline characteristics of the two groups were compared. At the end of the PCI procedure, angiographic features including TIMI flow grade, corrected TIMI frames count and resolution of the sum of ST-segment elevation 30 min after primary PCI were analyzed immediately. The occurrence rate of MACE (death, reinfarction, heart failure, and revascularization) at 6 months after procedure was also compared between groups. RESULTS A total of 79 STEMI patients comprised the study. There was no significant difference between groups in initial angiography before PCI and there was no significant difference between groups in TIMI flow grade, corrected TIMI frames count and resolution of the sum of ST-segment elevation 30 min after primary PCI. No significant difference was found in MACE rate between groups at 6 months after the procedure. CONCLUSION In patients with STEMI undergoing primary PCI, shuxuetong injection improves coronary flow and myocardial perfusion.