© 2018 American Journal of Preventive Medicine Introduction: Black patients who experience acute myocardial infarction and receive care in high minority-serving hospitals have higher readmission rates. This study explores how hospital system affiliation (centralized versus decentralized/independent) impacts 30-day readmissions after acute myocardial infarction in black men. Methods: In 2018, the Healthcare Cost and Utilization Project State Inpatient Database (2009–2013) was used to observe 30-day readmission for acute myocardial infarction by race, and data from the American Hospital Association Annual Survey of Hospitals (2009–2013) to determine hospital system affiliation for the states Arizona, California, North Carolina, and Wisconsin. A series of hierarchic logistic regressions were conducted to determine if hospital system affiliation mediates the relationship between race and 30-day readmission. Results: Of 63,743 hospitalizations for acute myocardial infarction among men between 2009 and 2013, black men accounted for 7.1% of hospitalizations and 8.0% of readmissions. In both models, race significantly predicted 30-day readmission (unadjusted OR=1.25, 95% CI=1.14, 1.37, p<0.001; AOR=1.13, 95% CI=1.03, 1.25, p=0.046). After controlling for system type, black men were more likely to be readmitted after acute myocardial infarction than white men in both models (unadjusted OR=1.25, 95% CI=1.14, 1.38, p<0.001; AOR=1.14, 95% CI=1.03, 1.25). There was no difference in odds of being readmitted by race and hospital system type (unadjusted OR=0.88, 95% CI=0.25, 3.07, p=0.84, AOR=1.02, 95% CI=0.21, 5.10, p=0.98). Conclusions: Black men appear to be more likely to be readmitted after acute myocardial infarction. Centralization does not appear to mediate the relationship between race and 30-day readmissions for acute myocardial infarction. Supplement information: This article is part of a supplement entitled African American Men's Health: Research, Practice, and Policy Implications, which is sponsored by the National Institutes of Health.