Background: Due to the non-specific clinical manifestations, neonatal sepsis (NS), one of the major concerns with considerable morbidity and mortality in newborn intensive care units (NICUs), poses a significant challenge for clinicians and the laboratory. Blood culture, non-specific biomarkers, and clinical presentation are currently used to diagnose newborn sepsis. Traditional biomarkers with low sensitivity and positive predictive value include total leucocytic count (TLC) and C-reactive protein (CRP). The aim of the current study is to evaluate the value of apelin, procalcitonin, and proadrenomedullin as biomarkers in the diagnosis of neonatal sepsis. Patients and methods:  This study was conducted, over a period of one year, at NICU in Minia University Hospitals on 60 neonates diagnosed as sepsis representing Group-I who were further sub-grouped into Group I-a (Early Onset sepsis) including 36 neonates and Group I-b (Late Onset Sepsis) including 24 neonates. A total of 30 apparently healthy neonates represented Group-II (control group) with no manifestations or laboratory findings of sepsis. Samples were collected from each neonate for CBC, CRP, blood culture and evaluation of serum procalcitonin, apelin and proadrenomedullin by ELISA. Results: Significant correlations were found between serum procalcitonin, apelin and proadrenomedullin with the routine investigations done (TLC, platelets count and CRP). Higher procalcitonin, proadrenomedullin and apelin levels were observed in septic group (early onset sepsis and late onset sepsis) with positive blood culture results. Staphylococcal infection was the most frequent type of infection. Conclusion: Measuring procalcitonin, apelin and proadrenomedullin levels are valid and can aid in the diagnosis of NS, but alone cannot be dependable for accurate diagnosis.