In contrast to younger patients, old peoples frequently mainfest more than one pathologic process, mainly degenerative diseases and neoplasia. Nearly all have some degree of arteriosclerosis, even if this is not clinically diagnosed, and many have associated chronic cardiac, renal, hepatic, or pulmonary disease. The surgeon and the anesthesiologist must see theat their clinical decisions are tied to a physiologic understanding based on exact quantification of the specific hemodynamic, respiratiory, renal, and metabolic factors which may play a decisive role in influencing the final outcome to a major operative procedure. From May 1972 to Dec 1980, the Department of Anesthesiology, Hanyang University, College of Medicine had 517 geriatric patients(above 65 years) who received anesthesia and these were analyzed clinically according to age, sex, department, physical status, anesthetic technique and agent, anesthesia time, length of admission, laboratory studies(chest X-ray, EKG, arterial blood gas), and postoperative complications(mortality and causes of deathe). The results are as follows. 1) Out of 25,857 anesthetized patients 517(2.0%) were over 64 years of age and 290 were males(56.1%) and 227 females(43.9%). 2) In the surgical group, 246 cases (47.6%) were from general sugery: 81 cases(15.7%), orthopedic surgery: 78 cases (15.1%), urology: and 67 cases (12.9%), neurosurgery respectively. 3) In the classification of physical status, 33 cases(6.4%) were class 1, 269 cases(52.0%) class 2, 181 cases (35.0%) class 3, 28 cases (5.4%) class 4, and 6 cases (1.2%) class 5. Emergency cases were 137 cases(26.5%) and 380 cases (73.5%) were elective. 4) Concerning premedication-150cases(29.0%) were premedicated with atropine sulfate plus valium and 93 cases had no premedication. 5) There were 425 cases of general anesthesia (82.2%) and 92 cases of regional anesthesia (17.8%). The major anesthetic was halothane, 362 cases (70.0%). The technic in 419 cases( 81.0%) was circle type with endotracheal intubation. Anesthesia duration was within 1hour for 70 cases(13.5%), within 2 hours for 158 cases(30.0%), and within 3hours in 144 cases(27.9%). 6) Preoperative laboratory findings were as follows: The chest X-ray suggested that 199 cases (45.9%) were within normal limits, 56 cases (12.9%) had hypertensive heart disease, 56 cases (12.9%) had pulmonary tuberculosis, and 38 cases (5.1%) had senile lung fibrosis. The EKG which was done on 85% of the patients, ravealed that 193 cases (44.0%) were within normal limits, 61 cases(13.9%) showed left ventricular hypertrophy, and 38 cases(8.7%) had myocardial ischemia. In the preoperative arterial blood gas studies of 56 cases the results were almost all within normal limits. 7) Postoperative complications were as follows: 52 cases showed wound infection or bleeding, 20 cases had pneumonia, and 18 cases atelectasis. There were a number of miscellaneous complications. 8) The overall mortality rate was 5.8%. The difference of mortality rate related to the age was not statistically significant,(p>0.1) and the mortality rate related to physical status was statistically significant(p<0.005). 9) As the cause of death-11 cases (36.7%) had transtentorial herniation, 2 cases (6.7%) sepsis, 2 cases (6.7%) hypovolemia, and 1 case (3.3%) had pulmonary edema.