Background and objectives: Most patients with chronic cardiovascular diseases experience decreased libido and frequency of sexual activity, as well as Erectile dysfunction (ED). The IIEF is multidementional scale for assessment of erectile function and is composed of 15-item questionnaire of five relevant domain of sexual function: erectile function (EF), sexual intercourse satisfaction (IS), orgasmic function (OF), sexual desire (SD), overall satisfaction (OS). This study tried to investigate the prevalence of erectile dysfunction (ED) in patients with cardiac disease. Methods: A total of 62 men(mean 57.1짹8.53 years, range 34 to 75 years) with cardiac disease who had regular outpatient clinic follow up were evaluated about their sexual function with Korean version International Index of Erectile Function (IIEF) questionnaire. Results: The overall frequencies of sexual dysfunction were 100% in all five relevant domain of sexual function. The frequencies of moderate or severe sexual dysfunction in cardiac patients were 45.2% in EF, 25.8% in IS, 46.8% in OF, 56.5% in SD, and 61.3% in OS. Conclusions: This study showed higher frequencies of sexual dysfunction in comparison to the results of previous reports. Accordingly, it is important for physicians dealing with patients with cardiovascular diseases to address sexual concerns in their patients. After careful evaluation, most patients with stable cardiac disorders can resume sexual activity and/or can be treated for ED.