Objectives To investigate the association between hospital safety culture and 30‐day risk‐adjusted mortality for Medicare patients with acute myocardial infarction (AMI) in a large, diverse hospital cohort. Subjects The final analytic cohort consisted of 19,357 Medicare AMI discharges (MedPAR data) linked to 257 AHRQ Hospital Survey on Patient Safety Culture surveys from 171 hospitals between 2008 and 2013. Study Design Observational, cross‐sectional study using hierarchical logistic models to estimate the association between hospital safety scores and 30‐day risk‐adjusted patient mortality. Odds ratios of 30‐day, all‐cause mortality, adjusting for patient covariates, hospital characteristics (size and teaching status), and several different types of safety culture scores (composite, average, and overall) were determined. Principal Findings No significant association was found between any measure of hospital safety culture and adjusted AMI mortality. Conclusions In a large cross‐sectional study from a diverse hospital cohort, AHRQ safety culture scores were not associated with AMI mortality. Our study adds to a growing body of investigations that have failed to conclusively demonstrate a safety culture–outcome association in health care, at least with widely used national survey instruments.