Diabetic cardiomyopathy is characterized by a prominent interstitial fibrosis. Postulated etiologies include microangiopathy, autonomic neuropathy, and metabolic factors. A common root of these pathologies is hyperglycemia or hyperinsulinemia, both of which are prominent in type 2 diabetes mellitus, which has the highest incidence of cardiovascular morbidity and mortality. The relative importance of each factor is a matter of debate; it is likely that both of these factors in addition to the concomitant risk factors seen in diabetics (dyslipidemias, hypertension, obesity, coagulation abnormalities) contribute to the spectrum of myocardial disease in diabetes. A discussion of these contributive pathologies and the hyperglycemia and hyperinsulinemia that underlie them is the subject of this review. Treatment methodologies to control the development of such pathology also are discussed.