Reference interval in biochemistry laboratories provides guidelines to the clinicians to interpret the client's results. A population of 120 healthy individuals are required in establishing reference ranges to achieve the required and acceptable statistical confidence as per National committee of clinical laboratory standard. To establish the reference ranges for paediatrics and young adults (below 17 years) posse challenges for this category, ethical clearance and need of consent from the guardian for the subject under the study. The main aim of this research was to establish the paediatric reference ranges for renal, cardiac and pancreatic function for young adults in Taita Taveta Population. A prospective study was carried out on 577 healthy young adults and paediatric population from Taita Taveta County, Kenya. Study findings reveal significant variations of renal, cardiac, and pancreatic reference ranges for Taita Taveta, Kenya compared to those supplied by the manufacturers together with the reagent kits in addition to those in literature done in the western world. It is in tandem with findings done in many other studies. This study therefore confirms the need for laboratories to develop their own reference values for their own populations.