The lower incidence of cardiovascular disease in premenopausal women than in men disappears after the onset of menopause. Diabetes mellitus increases the risk for cardiovascular disease in women and any advantage due to the premenopausal period that would exist is eliminated. Nevertheless, the mechanisms by which diabetes impairs the vascular function is well demonstrated in males, but only a few studies in the field have employed female subjects. These mechanisms may not, however, be exactly the same in females and a better understanding of the mechanisms involved in the vascular dysfunction in diabetic females should allow the development of pharmacological therapies for cardiovascular patients of both sexes. Therefore, the purpose of this review is to summarize the endothelial factors involved in the vascular dysfunction of diabetic female animals and diabetic women. Nitric oxide, reactive oxygen species, and prostanoids are emphasized.