Transradial access (TRA) has emerged as an alternative to transfemoral access (TFA) for percutaneous coronary intervention (PCI) in ST elevation myocardial infarction (STEMI) patients. However, the rate of TRA adoption has been much slower in the acute coronary syndrome (ACS) patient population. This meta-analysis was conducted to assess clinical outcomes of TRA compared to TFA in STEMI. A manual search of PubMed, EMBASE, Cochrane library database, Cumulative Index to Nursing and Allied Health Literature (CINAHL), ClinicalTrials.gov and recent major scientific conference sessions from inception to October 15, 2019 was performed. Primary outcomes in our analysis were all-cause mortality and trial-defined major bleeding. Secondary outcomes included vascular complications, myocardial infraction, stroke, procedure, and fluoroscopy time. 17 randomized controlled trials (RCTs) (N=12,018) met inclusion criteria. TRA was associated with lower all-cause mortality (RR: 0.71, 95%CI: 0.57 – 0.88), major bleeding (RR: 0.59, 95%CI: 0.45 – 0.77) and vascular complications (RR: 0.42, 95%CI: 0.32 – 0.56) compared with TFA. There was no difference in the incidence of MI, stroke, or procedure duration between the two groups. The difference in all-cause mortality between TRA and TFA was statistically non-significant when major bleeding was held constant. In conclusion, TRA was associated with lower risk of all-cause mortality, major bleeding, and vascular complications compared with TFA in STEMI patients undergoing PCI.Copyright © 2020. Published by Elsevier Inc.