Introduction: The presence of concomitant erectile dysfunction (ED) with heart failure (HF) is not surprising, because endothelial dysfunction is pathophysiologic signature of both ED and HF. ED significantly and adversely affects quality of life in patients with HF. It was demonstrated that ivabradine treatment can improve endothelial function and ED in experimental models. In this study, we aimed to determine the effect of ivabradine treatment on ED in patients with HF via International Index of Erectile Function (IIEF-5) questionaire.Material and methods: Consequently, 29 patients, between 18 and 70years of age, male with chronic HF known for at least 1year, New York Heart Association functional class I-II, left ventricule ejection fraction less than 40%, in sinus rhythm with a resting HR of at least 70 beats per minute (b.p.m.), who were intended to be treated with ivabradine according to the decision of their physicians were evaluated to determine ED. We used the Turkish version of the IIEF-5 questionnaire to evaluate ED on the last 6-month period. Twenty-four of 29 patients who scored 21 were considered to have ED and included to the study. IIEF-5 scores for each question and domains were calculated for all responders at baseline and at 6-month follow-up visit in order to determine any effect of ivabradine treatment on ED in patients with HF.Results: According to the data of survey, Cronbach's alpha coeffient for all of the patients who were included into the study were 0.84 and detected highly reliable. IEFF-5 questionnaire scores increased significantly (p=.003) after the ivabradine treatment, on the contrary, significant decrease in HR was revealed as expected. HR is decreased steadily after ivabradine treatment and mean decrease in HR was 11.59.4 in this study population. Likewise, negative correlation was demonstrated between decrease in HR (p<.001) and increase in IEFF-5 scores (p=.003).Conclusion: Although lack of patients with HF have been evaluated in this study population, initial results seem promising that ivabradine has favorable effects on ED. These findings were postulated to be dependent exclusively on HR reduction. As a sequel, cardiologist should avoid neglecting ED to improve medical compliance as well as quality of life in patients with heart failure. This pilot study provide some data for further randomized controlled studies.