© 2018, Professional Medical Publications. All rights reserved.Objectives: Neutrophil-to-Lymphocyte Ratio (NLR) and Mean Platelet Volume (MPV) have been found to be useful indexes for the diagnosis of sepsis in adults. However, the knowledge of their roles and cut-off values in pediatric patients is limited. The primary objective of this study was to assess the ability of NLR and MPV to predict sepsis in children. A secondary aim was to evaluate the comparison of these parameters with C-reactive Protein (CRP). Methods: The study was conducted on pediatric patients, who had two or more of the following criteria were included in the study: tachycardia, tachypnea, temperature change, leukocytosis, or leukopenia for age. Patients were classified into sepsis and non-sepsis groups. The sepsis group was defined as the presence of two or more age specific Systemic Inflammatory Response Syndrome (SIRS) criteria and increased Procalcitonin (PCT) level (>0.5 ng/ml) Result: The median age of the study population was 18 (6-169) months. Two hundred-sixty four episodes of sepsis were recorded in 125 patients. Eighty two were classified as sepsis and 182 as non-sepsis. CRP level and MPV value were significantly higher in the sepsis group compared to non-sepsis group. The median CRP level was 47.8 mg/dl (10.2-119.5) in the sepsis group and 18.6 mg/dl (4.9-66.1) in the non-sepsis group (p=0.006). In the sepsis group, the median MPV value was 8.4 (7.6-9.5) and it was 7.8 (7.1-8.5) in the non-sepsis group (p=0.001). Significant correlations were found between the procalcitonin (PCT) and CRP level (p<0.001; r = 0.279), NLR (p=0.02; r = 0.186) and MPV (p<0.001; r = 0.243). MPV had the highest specificity for predicting sepsis (75.8%). The largest AUC was 0.629 with a cut-off value 8.5 for MPV, while the AUC was 0.557 with a cut-off value 1.97 for NLR and 0.606 with a cut-off value 38.9 for CRP. Conclusions: NLR and MPV values should alert clinicians to the possibility of sepsis and to initiate or change antibiotic treatment.