Background & objective: Depression associate with increase severity of illness, length of hospitalization and mortality in heart failure patient's .The aim of this study was to investigate the frequency and related factors of depression in male systolic heart failure patients. Materials & Methods: This is a cross sectional study that was conducted on 100 male patients with systolic heart failure in Alborz of Karaj and Shahriar Social Security Hospitals in 2010. Sampling method in this study was Convenience sampling. Data collected by demographic data form, MLHFQ (Minnesota Living with Heart Failure Questionnaire), (CES-D) Center for Epidemiologic Studies Depression Scale .Data was analyzed by SPSS software version 18 and using descriptive statistics, t-test, ANOVA and coefficient Pearson correlation. Results: The findings indicated that mean score of depression was 20.3±12 .47% had severe and 16% had mild to moderate depression. Depression significant associated with age(p=0.002), education(p<0.001), economic status(p=0.002), smoking(p=0.034), hemoglobin level(p=0.004), left ventricular ejection fraction(p=0.012), use of digoxin(p=0.019), angiotensin receptor blocker (ARB)(p=0.005), aldacton (p=0.005)and quality of life(p<0.001). Conclusion: Depression was common among men with systolic heart failure and had negative impact on quality of life. Nurses by screening and assessment symptoms of depression and refer patients for counseling and treatment can help to improve quality of life in heart failure patient.