The most common features of insulin resistance syndrome are obesity, insulin resistance/hyperinsulinemia, dyslipidemia, impaired glucose intolerance, and hypertension. A causal link between hypertension and insulin resistance has not been clearly established, but several lines of evidence suggest that insulin resistance and the resultant hyperinsulinemia are causally related to hypertension. The Wistar fatty rat develops hyperglycemia, hyperlipidemia, and hyperinsulinemia as features of insulin resistance followed by slight hypertension. Several studies indicate that insulin resistance is one of the pivotal factors for hypertension in Wistar fatty rats. Further studies on Wistar fatty rat are expected to elucidate the mechanism of hypertension induced by insulin resistance and suggest on approach to treat hypertension in obese or type 2 diabetes.