OBJECTIVE: To investigate the effects of nicorandil and tirofiban on no-reflow and postoperative outcome in patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention. STUDY DESIGN: A total of 438 patients with ACS diagnosed by the second Hospital of Shanxi Medical University from January 2019 to December 2020 were divided into two groups: nicorandil group (n=223) and tirofiban group (n=215). The nicorandil group was injected with 2 mg nicorandil 2 mm before coronary occlusion before balloon dilation, and the tirofiban group received 10 µg/kg intravenous injection during operation. Measurement of thrombolysis grade (thrombolysis in myocardial infarction [TIMI]), corrected TIMI frame count, and major adverse vascular events were recorded 30 days after operation in patients with ACS. RESULTS: Both nicorandil and tirofiban could improve the TIMI grade, and TIMI grade 3 blood flow was obtained in 190 cases (85.2%) and 175 cases (81.4%), respectively. There was no significant difference in the incidence of major adverse cardiac events (14.3% vs. 13.5%, score 0.13). CONCLUSION: Intracoronary use of nicorandil in patients with ACS can improve coronary perfusion, but the improvement of prognosis needs further study. © Science Printers and Publishers, Inc.