Objective: Long-term outcomes of vein morphologies in the endoscopic vein harvesting setting are lacking. We analyzed 15-year follow-up for endoscopic versus open vein harvesting and associated vein morphology outcomes in coronary artery bypass grafting at a single center. Methods: This single-center, prospectively collected, retrospective, observational study evaluated 15-year major adverse cardiovascular events (MACE) of endoscopic versus open vein harvesting and associated vein morphologies. Results: Among 729 patients, no differences were found between endoscopic and open vein harvesting in MACE hazard ratios despite increased risks with native Hawai’ian, Pacific Islander, and Filipino patients. Asian and Filipino patients had more thin-walled veins and Asian and multirace patients had more vasovasoral branches than White patients. Bifid veins were associated with increased risk of cardiac catheterization. Varicose veins were associated with myocardial infarction, congestive heart failure, and death. Thick-walled veins were associated with revascularization and dense adhesions with cardiac catheterization and revascularization. Conclusions: Fifteen-year adjusted MACE was similar between endoscopic and open vein harvesting in small coronary targets despite increased risks with native Hawai’ian, Pacific Islander, and Filipino patients. Bifid, varicose, thick-walled veins, and dense adhesions had worse MACE.