This study aimed to investigate the relationship between death anxiety and QoL in a sample of Iranian heart failure (HF) patients. A cross-sectional correlational design was employed to examine this relationship in a sample of 296 HF patients. Participants were recruited using convenience sampling from teaching hospitals in Kermanshah City, western Iran, between October and December 2023. Data were collected using a demographic questionnaire, the Templer Death Anxiety Scale (TDAS), and the Minnesota Living with Heart Failure Questionnaire (MLHFQ). Participants reported moderate to high levels of death anxiety (Mean [SD] = 7.54 [2.35]) on the TDAS and moderate to poor QoL (Mean [SD] = 36.24 [12.26]) on the MLHFQ. The statistical methods used in this study included descriptive statistics, independent t-tests, one-way analysis of variance (ANOVA), Pearson correlation coefficient, multiple linear regression analysis, and the Kolmogorov-Smirnov test. All statistical analyses were performed using SPSS version 26, with a significance level set at 0.05. A significant positive correlation was found between death anxiety and QoL (r = 0.329, p < .001), indicating that higher levels of death anxiety were associated with lower QoL. These results underscore the importance of addressing death anxiety in HF patients to improve their QoL. Interventions targeting the reduction of death anxiety and the enhancement of QoL are essential for optimizing care for this vulnerable population. The study recommends the implementation of psychological interventions, support groups, comprehensive counseling, education, and regular assessments for this purpose.