AIM: The aim of this research was to verify the reliability of application of PIM2 scoring system on children treated in Intensive Care Unit of the Department Pediatrics of University Hospital Centre in Split. METHODS: The research included children treated within Pediatric Intensive Care Unit of University Hospital Centre in Split. The data on these children needed to perform a calculation using PIM2 system were prospectively collected from January 2005 until December 2011. The data on 2003 hospitalised patients, divided into 6 diagnosticrelated groups, have been included and analyzed in this research. We were determining PIM2 values and system`s discriminatory and caliber ability for the whole population of patients and also for the specific diagnostic-related groups. Furthermore, we calculated the standardized mortality ratio. RESULTS: The results have shown a high assessment accuracy of estimating the mortality rate of our population by using PIM2 system. CONCLUSION: PIM2 is a system which can be applied with excellent results on studied population and that is why we highly recommend its regular use in all Pediatric Intensive Care Units.