Heart failure is a prolonged and progressive syndrome that leads to low quality of life and hospital readmissions. Avoiding or early recognizing health problems in heart failure is associated with proper self-care and recovering overall health-related quality of life. To describe the self-care behaviors and association of sociodemographic and clinical factors that affect patients’ quality of life. The quantitative, cross-sectional convenience sample technique was used to collect 200 patients diagnosed with heart failure admitted to Sulaimani Cardiac Hospital, Iraq, from January to May 2022. The data were collected through direct interviews, a validated questionnaire, and the Self-Care of Heart Failure Index. About 50% of the participants were aged 62- 77 years, 65.5% were males, 66% were illiterate, and 65.5% had a low economic state. According to the classification of the New York Heart Association, 48% of them were class III heart failure. The mean scores of 1.67, 1.56, and 1.80 were observed on self-care confidence, poor self-care management, and poor self-care maintenance using the Self-Care of Heart Failure Index without significant difference (p≤0.05). The outcomes of this study demonstrated that most patients had inappropriate scores in self-care maintenance, management, and confidence subscales. The study also found that higher scores were associated with certain factors, such as age group, residence, number of recent hospital admissions for heart failure, and severity of heart failure.