Abstract Objective: We compared percutaneous coronary intervention (PCI) with coronary artery bypass grafting (CABG) for the treatment of left main coronary artery (LMCA) disease by conducting a systematic review and meta-analysis of randomised controlled trials (RCTs). Methods: RCTs of PCI versus CABG in patients with LMCA stenosis were identified from MEDLINE, the Cochrane Library and search of bibliographies to November 2016. Study-specific HRs with 95% CIs were aggregated for all-cause mortality, major adverse cardiac and cerebrovascular events (MACCE), and other cardiovascular events at time points of 30 days, 1 year and 3 years and beyond. Results: Six RCTs comprising 4700 patients were included. There were no significant differences in risk of all-cause mortality in pooled analysis of relevant trials at 30 days (0.61, 95% CI 0.27 to 1.36), 1 year (0.66, 95% CI 0.42 to 1.04), and 3 years and beyond (1.04, 95% CI 0.81 to 1.33), comparing PCI with CABG. There was no significant difference in the risk of MACCE at 30 days (0.72, 95% CI 0.51 to 1.03) and 1 year (1.16, 95% CI 0.94 to 1.44); however, PCI was associated with a higher risk of MACCE compared with CABG during longer-term follow-up (1.27, 95% CI 1.12 to 1.44). Composite outcome of death, stroke or myocardial infarction was lower with PCI at 30 days (0.67, 95% CI 0.49 to 0.92). Repeat revascularisation was increased at 1 year and at 3 years and beyond for PCI. Conclusions: All-cause mortality rates are not significantly different between PCI and CABG at short-term and long-term follow-up. However, PCI is associated with a reduction in the risk of major cardiovascular outcomes at short-term follow-up in patients with LMCA stenosis; but at long term, MACCE rate is increased for PCI.