Background and Objective: According to the fact that neonatal infection is a challenging diagnosis field, several studies have tried to test sensitivity and specificity of diagnostic tests. This study was conducted to evaluate the sensitivity and specificity of procalcitonin (PCT) as a single early marker of neonatal sepsis. Materials and Methods: In this study, 150 neonates admitted to NICU and neonatal ward in Shahrekord Hajar hospital were enrolled. A full workup including blood cultureand other tests and PCT was conductede. Sensitivity, specificity, positive and negative predictive values for PCT was determined. Results: It was found out that 8 patients had definite infection, 15 patients had possible infection, and 127 patients had no infection. Although PCT was not able to significantly differentiate between those with definite and possible infections (p>0.05), but there was a significant difference for frequency of abnormal PCT between non-infectious patients and other patients. Sensitivity, specificity, positive and negative predictive values of PCT was 87.5%, 87.4%, 30.4%, 99.1%, and 87.41% respectively. Conclusion: Beside the limitation of the sample size, the satisfactory diagnostic characteristics of PCT highlight it as a good measure for diagnosis of neonatal sepsis. Further studies are essential to be carried out.