Owing to a large-jeopardized myocardium, left main coronary artery disease (LMCAD) represents the substantial high-risk anatomical subset of obstructive coronary artery disease. For several decades, coronary artery bypass grafting (CABG) has been the "gold standard" treatment for LMCAD. Along with advances in CABG, percutaneous coronary intervention (PCI) has also dramatically evolved over time in conjunction with advances in the stent or device technology, adjunct pharmacotherapy, accumulated experiences, and practice changes, establishing its position as a safe, reasonable treatment option for such a complex disease. Until recently, several randomized clinical trials, meta-analyses, and observational registries comparing PCI and CABG for LMCAD have shown comparable long-term survival with tradeoffs between early and late risk-benefit of each treatment. Despite this, there are still several unmet issues for revascularization strategy and management for LMCAD. This review article summarized updated knowledge on evolution and clinical evidence on the treatment of LMCAD, with a focus on the comparison of state-of-the-art PCI with CABG.