Testosterone deficiency syndrome (TDS) induces several negative effects that generally involve different organs such as testis, bone, skeletal muscle, and heart, leading to reduction in testis function, causing osteoporosis, strongly reducing muscle mass, decreasing exercise capacity and strength and facilitating heart failure. Approximately 25% of patients affected by chronic heart failure (CHF) is characterized by plasma Testosterone (T) levels below normal ranges also related to disease progression. In addition, reduction of circulating testosterone levels may contribute to some specific features of CHF, such as abnormal energy handling, weakness, dyspnoea and cachexia in particular. According to some recent evidence it has emerged that testosterone replacement therapy (TRT) may improve muscle strength and functional pulmonary capacity in CHF men with TDS. This review will place emphasis on the pathophysiological role of testosterone deficiency in CHF men as well as the effects of the testosterone replacement therapy.