Prognostic significance of coronary circulation dominance remains controversial. The primary objective of this meta-analysis was to pool all the available evidence to assess the influence of left coronary dominance (LD) on outcomes in patients who underwent percutaneous coronary intervention (PCI). MEDLINE, Cochrane CENTRAL, and Scopus databases were searched for all observational studies and randomized controlled trials that investigated the association between coronary dominance and outcomes in patients who underwent PCI. Odds ratios (OR) and 95% confidence intervals from individual studies were pooled using a random effects model. A total of nine studies including 266,119 patients were included. On pooled analysis, it was noted that LD was associated with significantly increased odds of in-hospital (OR: 1.54 [1.12, 2.11]; p = 0.007), 30-day (OR: 2.16 [1.22, 3.84]; p = 0.008), and long-term mortality (OR: 1.83 [1.33 to 2.50]; p < 0.001). LD patients also experienced a significantly higher incidence of major adverse cardiac events (OR: 1.27 [1.03, 1.58]; p = 0.03) and failed PCI (OR: 1.30 [1.03, 1.65]; p = 0.03). In contrast, no significant difference was noted between LD and non-LD patients in the incidence of stent thrombosis (OR: 1.28 [0.55, 3.01]; p = 0.57; I2 = 0%) or reinfarction (OR: 1.73 [0.90, 3.35]; p = 0.10; I2 = 63%). In conclusion, this meta-analysis suggests that patients with LD coronary anatomy are at significantly increased risk for mortality after PCI compared with patients with a non-LD anatomy.