Objectives: To identify whether social vulnerability is associated with low cardiac rehabilitations (CR) use, a Class I recommendation by current treatment guidelines following acute myocardial infarction (AMI). Methods: We performed this cross-sectional study using the 2017 Behavioral Risk Factor Surveillance System (BRFSS) survey. The Centers for Disease Control and Prevention Social Vulnerability Index (CDC SVI) was calculated using 15 social risk factors from 4 main themes including socioeconomic status, household composition and disability, minority status and language, and housing type and transportation. A higher SVI indicates higher social vulnerability. We used multivariable logistic regression models to evaluate the association of CR use with state-level SVI adjusted for demographic, behavioral, socioeconomic, and comorbidity variables. Results: A total 2093 participants with history of AMI were included. Out of total, 61.7% were older than 65 years, 42.5% female, 72.5% White, and 42.4% used CR. Participation in CR was lower among females (odds ratio [OR], 0.64; 95% confidence interval [CI], 0.44–0.91), those without a primary care physician (OR, 0.45; 95% CI, 0.23–0.87), and higher with college degree education (OR, 1.95; 95% CI, 1.06–3.59). CR use decreased with increasing SVI tertiles (1st =61%, 2nd =52%, and 3rd =35%). Compared with those residing in states in the 1st tertile, CR use was lower in the 2nd (OR, 0.68; 95% CI, 0.47–0.98) and 3rd (OR, 0.33; 95% CI 0.23–0.48) SVI tertiles. Conclusion: CR use following AMI is low and is associated with social vulnerability. Identifying social risk factors may help improve access to care among vulnerable populations.