Abstract: Testosterone has important effects on human body metabolism, physiology and cardiac pathology. Higher concentrations of testosterone or its chronic effects can increase T- and L-type calcium channel density and lower concentrations or acute effects can block T- and L-type calcium channels, reduce male Q-Tc period and improve sensitivity to insulin and lipid metabolism. Testosterone can increase calcium regulatory proteins and expression of beta-2 receptor, enhance calcium transit rate and reduce calcium overload in case of increase of intracellular calcium concentration. Appropriate concentration of testosterone can sustain a certain vascular tension, improve cardiac conduction or dilate coronary arteries, reduce insulin resistance and incidence of metabolic syndrome, improve myocardial ischemia, reduce apoptosis and myocardial cell fibrosis, protect the heart and enhance cardiac diastolic efficiency.