The general intensive care unit of Presbyterian Medical Centar was opened in 1965 with 3 beds and expanded to 17 heds in 1981. Generally, the type of I.C.U. is multidisciplinary and intensive care often means a combination of recovery room service and intensive therapy. Here, we have analyzed clinically 4, 986 LC.U. patients admitted between Jan. 1986 and Dec. 1990. to obtain a better guide and management in the I.C.U.. The results were as follows I) Total number of patients for 5 years was 4,986; 1,071 patients in 1986, 1,102 patients in 1987, 1,012 patients in 1988, 952 patients in 1989, 849 patients in 1990. The ratio of male to female patients was almost 2: 1. 2) Total admission days in the I.C.U. was 26,892 days and average patient stay being 5.5 days. The average age for 5 years was 50.9 year-old-age. 3) The majority of the patients(3,526 cases, 70%) stayed in the I.C.U. less than 5 days The number of patients staying more than 9 days increased from 127 cases(12%) in 1986 to 155 cases (18%) in 1990 4) The group representing the highest number of patients admitted was in the 50 to 59 year-old-age group. About 60% of the patients admitted were in the 40 to 69 year-old-age groups and the highest mortality rate occurred in the 70 to 79 year-old-age group(24.4%). 5) The number of the patients admitted to the department of internal medicine, which was the highest among all departments, was 3,564 caaes. Mortality rate was highest in the department of pediatric. 6) During 5 years, overall mortality rate was 21.9%(1,091 cases) inclusive of the hopeless-dis-charged patients. 7) Liver cirrhosis & variceal rupture of esophagus was the commonest disease. Mortality rate WS8 highest in leukemia(50%) & lymyhoma(50%) and lowest in acute renal failure(0%). 8) After putting into operation of nation-wide medical. insurance scheme, average patient stay and average age were increased. From the above results, it can be concluded that average admission days, average age and patients staying more than 9 days in the I.C.U. increased annually.