Cocaine is an established cardiovascular toxin, but the impact of cocaine use on clinical outcomes in heart failure (HF) remains unknown. Although nonselective β-blocker use in cocaine users with HF and reduced ejection fraction (HFrEF) appears to be safely tolerated, selective β-blockers have not been evaluated. This study aimed to assess whether cocaine use is associated with worse clinical outcomes in patients with HF and evaluate the safety of β-blocker prescription upon discharge in cocaine users with HFrEF. This was a single-center retrospective cohort study of patients with incident HF hospitalization at a safety-net hospital. Primary outcomes included all-cause mortality and readmissions, including HF. Cocaine users were compared with nonusers matched by age, gender, and year of index admission. In cocaine users with HFrEF, outcomes were compared according to β-blocker prescription at discharge. From 2001 to 2019, 738 cocaine users were identified and compared with 738 matched nonusers. Cocaine use was associated with increased mortality (adjusted hazard ratio [HR] 1.21; 95% confidence interval [CI] 1.00 to 1.48) and 90-day readmission (all-cause: adjusted HR 1.49; 95% CI 1.20 to 1.85; HF: adjusted HR 1.49; 95% CI 1.10 to 2.01), persisting at 1 year. In cocaine users who were prescribed metoprolol, carvedilol, or no β-blocker at discharge, the rates of 1-year mortality and 30-day readmission were similar. In conclusion, cocaine use is associated with increased all-cause mortality, HF readmission, and all-cause readmission. Both nonselective and selective β-blocker may be safe in managing patients with HFrEF and cocaine use.