Background: Heart failure (HF) in older adults is often associated with preserved left ventricular systolic function (LVSF). The objective of this retrospective follow-up study was to determine the correlates and outcomes of preserved LVSF among older adults hospitalized with HF. Methods: We studied older Medicare beneficiaries hospitalized with HF (n = 1091) who had documented LVSF evaluation (n = 438). LVSF was defined as preserved if left ventricular ejection fraction was ≥40%. The Fisher exact test and the Student t test were used to compare baseline characteristics between patients with preserved versus those with impaired LVSF. Multivariate logistic regression analysis was used to determine the correlates of preserved LVSF. Cox proportional hazards analyses were used to determine the associations between LVSF and both 4-year mortality rates and 6-month readmission rates and the associations between angiotensin-converting enzyme (ACE) inhibitor use and 4-year mortality rates, separately, in patients with preserved and impaired LVSF. Results: Of the 438 patients, 200 (46%) had preserved LVSF. Women were more likely to have preserved LVSF (odds ratio [OR] = 2.44, 95% CI 1.57-3.81) than men. Preserved LVSF was associated with lower 4-year mortality rates (adjusted hazards ratio [HR] = 0.67, 95% CI 0.52-0.86) but not with 6-month readmission rates (adjusted HR = 0.66, 95% CI 0.41-1.09). The use of ACE inhibitors was associated with lower 4-year mortality rates in patients with impaired LVSF (adjusted HR = 0.61, 95% CI 0.43-0.86) but not in those with preserved LVSF (HR = 0.96, 95% CI 0.65-1.42). Conclusions: Among older adults hospitalized with HF, preserved LVSF was common among women and was associated with significantly higher morbidity and mortality rates, which were unaffected by treatment with ACE inhibitors.