Numerous existing Pediatric Early Warning Scores (PEWs) have varying degrees of reliability and validity, which are used in variety diseases of patients. This study is a prospective diagnosis study which involved the pediatric nurse evaluation of patient status using modified Pediatric Early Warning Score (NU-PEWS) until the patient was discharged or transferred to PICU. A total of 824 pediatric patients were admitted, 407 participants were enrolled in this study. The NU-PEWS demonstrated the most accurate cut-off point at greater than 3, with 90.5% sensitivity and 89.1% specificity. The receiver operating characteristic (ROC) indicated positive results in the general medical condition (ROC 0.958), gastrointestinal, respiratory, and hematologic diseases (ROC 0.94-0.97) whereas lowest in neurological disease (ROC 0.843). This study validated that NU-PEWS has good performance in detecting deteriorating patients, and that prediction utilizations are good in almost every subgroup of disease, with the exception of neurological disease.