The purpose of this population-based study was to examine health-related quality of life (HRQOL) and functional status among breast cancer survivors with heart failure. We examined Medicare Health Outcomes Survey data from women aged 65 and older diagnosed with breast cancer in the past 5years. Surveys were linked to Surveillance, Epidemiology, and End Results cancer registries. Each woman identified with self-reported heart failure (n=239) was matched to controls without heart failure (n=685) using propensity scores. The Short Form-36/Veterans Rand-12 measured eight domains of HRQOL. Functional status impairment was measured by limitations in six activities of daily living (ADLs). Linear models estimated associations between heart failure status and HRQOL. Logistic regression models estimated odds ratios for associations between heart failure and ADL impairment. We examined associations for the total study population and subgroups stratified by cancer stage. Among all study participants, heart failure was associated with significant deficits in every HRQOL domain and impairment in all ADLs (p<0.01, ORs ranged from 1.74 to 2.47). After stratification by cancer stage, heart failure was associated with physical HRQOL deficits across all cancer stages (physical function, vitality, general health) and mental HRQOL deficits only in women with stage I/II cancer (role-emotional, social function). Women with early stage cancer experienced the greatest HRQOL deficits associated with heart failure. Heart failure in breast cancer survivors is associated with substantial HRQOL deficits and functional status impairment, particularly in early stage cancer. Tailored interventions are needed to improve physical function and mental wellbeing in this high-risk population.