Prospective data from the Health and Retirement Study, a nationally representative study of older US adults, was analyzed to examine the relationship between optimism and heart failure, adjusting for sociodemographic, biological, behavioral, and psychological covariates. Higher optimism was associated with a lower risk of incident heart failure during the follow-up period, and these effects persisted when accounting for covariates. There was also evidence of a dose-response relationship: As optimism increased, risk of developing heart failure decreased monotonically. This is the first study to suggest that optimism is associated with lower risk for heart failure.