Gender-difference is thought to be an important factor in the pathogenesis of glucose metabolism. Imbalances in sex hormones, such as increasing levels of progesterone or testosterone, are associated with systemic insulin resistance. After menopause, women are at an increased risk to develop visceral obesity due to the loss of endogenous ovarian hormone production. On the other hand, insulin resistance caused excess secretion of androgen, leading to menstrual disorder in obese young female. For the better management of glucose intolerance in pregnancy, the diagnostic criteria for gestational diabetes was revised in Japan. Although glucose intolerance in pregnancy is usually recovered after delivery, the subjects who diagnosed gestational diabetes need to be followed for an early detection of type 2 diabetes development. In addition, gender-differences in living practice and attitude are related to their lifestyle, including diet and exercise, therefore, gender-specific medicine increasingly plays key roles in the treatment of diabetes.