This study was attempted to help in explore new direction about classification of the severity of the pediatric patients admitted at NICU. Data were collected from 230 patients who admitted at Neonatal Intensive Care Unit of 3 University hospitals and 1 General hospital during 7 months period from september 1, 2000 to April 30, 2001. The results were as follows: 1. The degree of severity of the pediatric patients admitted at NICU shown ranged 1-102 and averaged 17.7. 2. With the respect to the severity of the pediatric patients admitted at NICU, there were statistically significant relation in passing day(s) to admission(r=-.153, p=.020), hospital day(s)(r-.501, p=.000), gestational age(r=-.354, p=.000), birth weight(r=-.280, p=.000), Apgar score at 1 min and at 5 min(4=-.340, p=.000; r=-.322, p=.000), present body weight(r=-.151, p=.023). 3. The severity of the pediatric patients according to general characteristics, there were significant difference in admitting day of the patients(t=2.339, p=.020), Apgar score at 1min and 5min(F=7.893, p=.000; t=3.568, p=.001).