With the progress of medical science, the scope of open heart surgery has expanded. From 1975 through 1987, we operated on 114 consecutive patients aged 65 years and over with the aid of a cardiopulmonary bypass in the Department of Surgery, National Taiwan University Hospital. The annual number of these elderly patients has increased gradually, reaching 6.4% of the annual open heart cases in 1987. Eighty-six of our 114 patients were males and 28 were females. Their ages ranged from 65 to 88 years with an average of 68.5 years. Overall, 65 patients (57%) were operated on for coronary artery disease and/or its associated lesions; 41 (36%), for valvular heart disease; six, for aortic dissection; two, for cardiac tumor; and one, for congenital pulmonary stenosis. One patient had combined coronary artery disease and aortic dissection. The mortality for isolated coronary artery bypass surgery was 12%; for single valvular surgery it was 11%. The complexity of the surgical procedure increased the operative mortality. The overall mortality was 23.6% (27/114), with subsequent death in 5.7% during an average of 25 months of follow-up. Because of the degeneration of organ-systems in elderly patients, and its frequent association with poor cardiac reserve and other medical problems, these elderly cardiac patients should be checked thoroughly before they are considered for open heart surgery. Our experience suggests that open heart surgery can be done in selected patients aged 65 years or older with acceptable risks. Age alone should not be an absolute contraindication to surgery, and clinical improvement is to be expected after surgery.