Background: This study was aimed to determine the accuracy of neutrophil gelatinase-associated lipocalin (NGAL) measurements, compared with serum measurements of procalcitonin, C-reactive protein (CRP), and white blood cell (WBC) counts, in predicting APN and associated renal problems in children with febrile UTIs. Methods: Total 138 children with their first febrile UTIs (59 APN, 79 lower UTI) were enrolled. Patients with renal failure, congenital urologic anomaly except vesicoureteral reflux (VUR), and recurrent UTIs were excluded. Serum levels of NGAL, procalcitonin, CRP and WBC counts were measured at admittance and analyzed. Laboratory, clinical, and imaging results were reviewed. Results: Receiver operating curve analyses showed NGAL (area under the curve (AUC) 0.893), procalcitonin (AUC 0.855), CRP (AUC 0.879), and WBCs (AUC 0.654) had good diagnostic profiles for identifying APN (all P 0.05). Using the best cut-off values (NGAL 117 ng/mL, procalcitonin 0.173 ng/mL, CRP 2.78 mg/dL, WBC 15,870/mm3), odds ratios for APN were all highly increased after adjusting for age and gender (NGAL 41.2, procalcitonin 22.8, CRP 25.3, WBC 4.2). The sensitivity and specificity of plasma NGAL for diagnosing APN was the highest among all examined biomarkers (sensitivity 88.1%, specificity 84.8%). Univariate analysis showed that female gender, NGAL, procalcitonin, CRP, and WBCs were associated with APN (all P 0.05). However, multivariate analysis revealed that only plasma NGAL was an independent predictor of APN ( P 0.001). NGAL, procalcitonin, and CRP levels also showed good predictive values for the presence of VUR (AUCs of NGAL, procalcitonin, and CRP 0.798, 0.756, 0.845). Conclusion: Plasma NGAL, procalcitonin and CRP are sensitive predictors for identifying APN and VUR. Plasma NGAL can be more reliable than serum procalcitonin, CRP, and WBCs in predicting APN in children with febrile UTIs