Aim: To compare between the expenses and benefits of procalcitonin testing in the diagnosis of early onset neonatal sepsis. Material and methods: This prospective observational study was carried out in the Department of Pediatrics, Anugrah Narayan Magadh medical college and hospital Gaya, Bihar, India for one year.100 Full-term neonates (>37 weeks gestational age) admitted to NICU with the clinical symptoms or signs of sepsis within 72 h of birth, and those with risk factors for EONS. For all patients included in the study, complete blood count with differential (CBC), CRP, blood culture, procalcitonin was done on admission to NICU, and was repeated after 8 hours from the initial one, while CRP was repeated after 24 hrs. Cultures from other sites (including CSF), chest x ray and imaging were done as appropriate. Results: 100 patients were included in the study, 70 females and 30 males. Their mean weight was 3.163 kg (range 2.1- 4.9 kg). About 89 (89 %) patients presented with more than one symptoms and signs of sepsis For CBC results, mean WBC count was 19.9± 10.1, the mean neutrophils count was 15.45± 11.57) and the mean platelet count was 168.21±70.21. The most frequent presenting sign was hypothermia (62%), hypoactivity and mottling (53%), followed by feeding intolerance (42%). Blood cultures were positive in 35 patients, who compromised the group of proven sepsis. Klebsiela was present in 13 patient, E coli in 9 patients, while group B streptococcus in 8 patients. Pseudomonas infection present in 3 patients, while MRSA (methicillin resistant staphylococcus aureus) was detected in 2 patients. The initial CRP (CRP1) , was non-reactive in 45 patients (45%), The initial procalcitonin in the sepsis group (PCT1), was non-reactive 45 patients (45%), <2.6 in 31 patients (31%), 2.6-10 in 19 patients (19%), and more than that in 5 patients (5%). The 35 patients in the group of proven infection (35%) were admitted for 10-14 days but 5 of them needed more than 2 WEEKS admission. The second group (not-proven infection) of 45 patients (45%) were discharged within 4 days of admission, and they did well on the follow up except for 8 patients who didn’t show up. The third group 20 patients (20%) suspected infection, treated with antibiotics for at least 10 days, and all of them did well on the follow up. CRP2 Sensitivity (92.5%), Specificity(53%), PPV(65.3%), NPV(86.5%) and PCT2 Sensitivity(95.8%), Specificity(87.7%), PPV(90.1%), NPV(98%). Conclusion: The expense of testing PCT twice is less than the expenses of one-day admission in NICU in developing countries. Application of such protocol could be of use in limiting period of stay in NICU.