As the population of obesity increases by the change of living habits, hypertensive prevalence increases in particularly middle-aged Japanese men. Obesity affects the development of hypertension and other metabolic risk factors. And the mechanism of development hypertension has been investigated from adipocyte standpoints. Recently, physiology or pathophysiology functions of adipocyte including TNF-alpha or leptin have been elucidated. Leptin makes sympathetic nerve activity by effects of the central nerve system. TNF-alpha induces insulin resistance. These effects cause hypertension. In particular, knowledge of insulin resistance has been clear by epidemiologic studies. Hypertension with obesity is often refractory, and it is poor prognosis. We have to develop an effective prevention and therapy in hypertension with obese subjects.