en Midwifery Orginal research <p><strong><em>Background:</em></strong> As a chronic disease, heart failure (HF) is a growing problem that not only impacts patients but also their family members and friends. Self-care is the main part of HF treatment. Despite the significance of determining variables involved in self-care, the relationships of self-efficacy, illness perception, and social support with self-care and the predictive roles of these variables in the treatment of HF have not been investigated.<br> <strong><em>Objectives: </em></strong>The present study was aimed at exploring the predictive roles of self-efficacy, illness perception, and social support in self-care of patients with heart failure.<br> <strong><em>Methods:</em></strong> In this predictive correlation study, 149 patients with HF were selected through convenience sampling from Tabriz Research Treatment Centre of Heart in 2016. To collect data, a demographic information questionnaire, self-care behaviour scale, general self-efficacy (GSE), brief illness perception questionnaire (Brief-IPQ), and social support scale were used. To analyse data, SPSS software version 16, descriptive statistics, Pearson correlation coefficient, and multiple stepwise regression analyses were employed.<br> <strong><em>Results</em></strong><strong>:</strong> Out of 149 subjects, 102 (68%) participants were male, and 47 (32%) of them were female. The mean and standard deviation of samples&rsquo; age were (64.40&plusmn;10.32) ranging from 37 to 88 years. Most of participants were married (82%)<span dir="RTL">.</span> The mean scores were as follows: Self-care (40.66&plusmn;13.16), self-efficacy (45.81&plusmn;22.03), illness perception (56.05&plusmn;18.24), and social support (49.09&plusmn;6.74). Data analysis demonstrated significant correlations between illness perception and self-care (p<0.001, r=0.649), self-efficacy and self-care (p<0.001, r=-0.678), social support and self-care (p<0.001, r=-0.518), and age and self-care (p<0.001, r=-0.506). The standardized coefficient of illness perception was (&beta;=0.274), social support was (&beta;=-0.237), self-efficacy was (&beta;=-0.230), and age was (&beta;=-0.211). In addition, 56% of self-care variance is explained by age, social support, self-efficacy, and illness perception.<br> <strong><em>Conclusion:</em></strong> All of the investigated variables were found to have a predictive role in self-care. Illness perception was recognized as the most effective factor in predicting self-care. Hence, illness perception can be used to explain 27% of self-care ability of patients with HF.<br> &nbsp;</p> heart failure, illness perception, self-care, self-efficacy, social support 39 46 http://nmcjournal.zums.ac.ir/browse.php?a_code=A-10-579-1&slc_lang=en&sid=1 Nastaran Mansoreyeh n.mansoreye1984@gmail.com 10031947532846007702 10031947532846007702 Yes PhD. Dept. of Health Psychology, Young Researchers and Elite Club, Tabriz Branch, Islamic Azad university,Tabriz,Iran Hamid Poursharifi PhD. Dept. of Psychology, Associated Professor, University of Tabriz, Tabriz, Iran 10031947532846007703 10031947532846007703 No PhD. Dept. of Psychology, Associated Professor, University of Tabriz, Tabriz, Iran Mohammadreza Taban Sadeghi 10031947532846007704 10031947532846007704 No MD, Dept. of heart, Assistant Professor, Tabriz University of Medical Sciences , Tabriz, Iran Mohammadreza Seirafi PhD. Dept. of psychology, Assistant Professor, Karaj Branch, Islamic Azad University, Alborz, Iran 10031947532846007705 10031947532846007705 No PhD. Dept. of psychology, Assistant Professor, Karaj Branch, Islamic Azad University, Alborz, Iran