To analyze the efficacy and adverse events (AEs) of pirfenidone in idiopathic pulmonary fibrosis (IPF) trials. Methods: MEDLINE, Cochrane Library, and ClinicalTrials.gov were searched for studies published before June 2016. All studies of clinical trials with the key words IPF or idiopathic pulmonary fibrosis or lung fibrosis and pirfenidone or Esbriet were identified. Quality assessment and data extraction nwere conducted by 2 independent researchers. A meta-analysis of randomized controlled trials (RCTs) was performed, and relative risk (RR) and 95% confidence intervals (95% CIs) were calculated. Results: Five studies were included in this review, involving 1568 participants. The meta-analysis revealed that pirfenidone reduced the risk of decline in forced vital capacity (FVC)% ≥10% from baseline (relative risk: 0.62; 95% CI: 0.51-0.76, p less than 0.001). The pirfenidone group had a significantly higher rate of AEs compared with the placebo group. Pirfenidone did not reduce mortality from any cause significantly (odds ratio: 0.63; 95% CI: 0.36-1.09). Conclusions: This study showed that pirfenidone could reduce disease progression as assessed by the decline in FVC in IPF. Pirfenidone represents a suitable treatment option for patients with IPF.