There is increasing evidence that endothelin-1 (ET-1) or related peptides play a prognostic value in coronary artery disease (CAD). The objective of this systematic review and meta-analysis was to evaluate the predictive role of ET-1 or related peptides in CAD patients. We comprehensively searched PubMed and Embase databases until January 15, 2023. Studies examining the association of ET-1, big ET-1, or C-terminal proendothelin-1 (CT-proET-1) level with all-cause mortality or major adverse cardiovascular events (MACEs) in CAD patients were included. Fourteen studies with 30,181 patients were identified. Comparison of the top and the lowest ET-1 level, the pooled risk ratio (RR) of all-cause mortality was 3.77 (95% confidence interval [CI] 1.59-8.94) for ET-1 and 1.65 (95% CI 1.25-2.18) for big ET-1. The pooled RR of MACEs was 2.24 (95% CI 1.85-2.72) for ET-1, 1.49 (95% CI 1.10-2.03) for big ET-1, and 3.55 (95% CI 2.12-5.96) for CT-proET-1, respectively. Subgroup analysis indicated that elevated ET-1 level was associated with 2.66-fold and 2.09-fold higher risk of in-hospital/30-day and long-term MACEs. Elevated ET-1, big ET-1, or CT-proET-1 may be independently associated with higher risk of all-cause mortality and MACEs in patients with CAD.