Coronary artery disease is present in 40-55% of patients with diastolic heart failure, and myocardial ischemia is both a cause and a precipitant of diastolic heart failure. Failure to recognize and treat acute and chronic ischemia in patients with this disorder results in rapid disease progression and poor outcomes. In diastolic heart failure patients without obstructive coronary artery disease, ischemia can be induced by other diseases that diminish perfusion gradient, cause myocardium to outgrow blood supply, or decrease diastolic filling time. In this article, we review the role of ischemia and development of fibrosis in the epidemiology, pathophysiology, and evaluation of patients with diastolic dysfunction and diastolic heart failure.