The objective of this study was to evaluate outcome for the patients of the intensive care unit, using APACHE III prognostic system. We prospectively collected the information of 429 patients in intensive care units at 2 tertiary care hospitals and 4 secondary care hospitals in PUSAN who had been admitted from December 1, 1993 to February 28, 1994. The results were as follows. 1. APACHE III scores were various from 0 to 173. But the distribution of the scores were similar between tertiary care hospitals and secondary care hospitals. 2. The mortality rate significantly increased as APACHE III score rised (p<0.001). Within the interval of same score, generally, the mortality of operative patients was higher in secondary care hospitals but in the case of nonoperative patients higher in tertiary care hospitals. 3. When the tertiary care hospitals compared with secondary for ratio of the predicted mortality rate to the actual mortality rate, there was little difference. 4. When we compared the 6 hospitals, one hospital had significantly better results and another hospital was significantly inferior (p<0.05).