Background: It is known to reduce the mortality when glutamine is supplied to patients during the surgery or in intensive care unit through intravenous nutrition supply. The purpose of this study is to establish the appropriate basis for use of glutamine and guidelines of nutrition supply for critically ill patients in the hospital by examining the clinical effects of administration of glutamine with subjects of elderly critically ill patients receiving intravenous nutrition in one hospital in Korea. Method: Among elderly patients with age of 60 or more hospitalized in Yeuido St. Mary's Hospital from August 2012 to July 2013, those who stayed in the intensive care unit for more than a week and received TPN (Total Parenteral Nutrition) for more than 3 days during staying in the intensive care unit were classified to a test group using glutamine and a control group without glutamine. Duration of use of mechanical ventilator, duration of hospitalization, occurrence of infectious disease and death were compared between two groups. We would like to identify the clinical test figures affected by the use of glutamine by examining changes in SCr, Total Protein, Albumin, AST, ALT, TB, DB and GFR at the time of admission and discharge. Results: At the time of admission to intensive care unit, gender, physical measurement information and clinical test figures did not show any significant difference between 72 subjects in a test group and 24 subjects in a control group. Thus, two groups began in the same condition. There were no significant difference in duration of hospitalization, duration of intensive care unit, use of mechanical ventilator, occurrence of infectious disease and death. As the results of statistical analysis of the average changes of clinical test figures at the time of admission and discharge of intensive care unit, SCr and GFR were significantly changed in the test group. GFR was significantly changed in a control group. As the result of analysis of the clinical test figures at the time of discharge with reflection of average changes after clinical test figures were corrected at the time of admission of intensive care unit, TB and GFR were significantly increased in a test group compared with those in a control group. Other clinical test figures were not significantly changed. Conclusion: If glutamine is administered to critically ill patients over age 60 receiving TPN and careful monitoring for total bilirubin is made in the future, it is expected to give the positive effect on renal function andminimize the side effect of arise in total bilirubin.