Since the discovery of leptin, numerous studies have established a central role for this adipose tissue hormone in the regulation of body weight. Further it is now recognized that obesity is a state of hyperleptinemia resulting from increased synthesis and release of leptin from the greater adipose tissue mass present in this condition. Leptin has been implicated in the regulation of a number of physiological processes in addition to body weight homeostasis, and in many cases the hyperleptinemia of obesity may result in pathologic consequences. Leptin appears to have a central role in the development of obesity related hypertension and a number of observations implicate leptin as contributing to atherogenesis and atherosclerosis. Although significant progress has been made in our understanding of the pathologic effects of leptin on cardiovascular function, additional work remains to be done to fully understand the consequences of hyperleptinemia on cardiovascular physiology.