The clinical course of patients with a previous coronary artery bypass graft surgery (CABG) presenting with non–ST-elevation myocardial infarction (NSTEMI) is not well defined. We aimed to compare the management and outcomes of patients with and without previous CABG who present with an NSTEMI. Patients hospitalized with an NSTEMI between 2002 and 2018 were identified from the National Inpatient Sample. The baseline characteristics and outcomes of patients with and without a previous CABG were compared. The outcomes included the rates of invasive procedures (defined as coronary angiography, percutaneous coronary intervention [PCI], or CABG), and its individual components, and in-hospital mortality. A total of 1,445,545 cases of NSTEMI were found, of which 133,691 (9.3%) had a previous CABG. Patients with a previous CABG were older (72.4 vs 68.6 years, p <0.001), more likely men (68.8% vs 56.9%, p <0.001), and of White race (79.7% vs 74.8%, p <0.001). The previous CABG cohort had lower rates of invasive procedures (50.4% vs 65.6%, p <0.001), PCI (23.7% vs 32.0%, p <0.001), or CABG (1.2% vs 10.6%; p <0.001) in the unmatched analysis. The results were consistent in the propensity score-matched analysis with the previous CABG group less likely to receive any invasive procedures (odds ratio [OR] 0.48, 95% confidence interval [CI] 0.47 to 0.49), including coronary angiography (OR 0.54, 95% CI 0.53 to 0.55), PCI (OR 0.66, 95% CI 0.64 to 0.67), or repeat CABG (OR 0.11, 95% CI 0.10 to 0.12). Moreover, the risk of in-hospital mortality was higher in the previous CABG group (OR 1.15, 95% CI 1.10 to 1.21). In the subset of patients who were revascularized in both groups, this excess mortality was no longer observed (OR 0.82, 95% CI 0.66 to 1.03). In conclusion, a previous CABG in patients who present with NSTEMI is associated with lower rates of invasive procedures and revascularization and higher in-hospital mortality than patients without a previous CABG.