We aimed to evaluate possible clinical application of urinary monocyte chemotactic protein-1 (MCP-1), osteopontin (OPN), and regulated upon activation, normal T-cell expressed and secreted (RANTES) chemokine as useful noninvasive markers in children with congenital hydronephrosis (HN) caused by ureteropelvic junction obstruction (UPJO).The study cohort consisted of surgical cases (study group 1), comprising 15 children with severe HN who required surgery (median age 1.03 years), conservative cases (study group 2), comprising 21 patients with mild, nonobstructive HN, and control group, comprising 19 healthy children. All children had normal renal function. Urinary (u) concentrations of MCP-1, OPN, and RANTES were measured using immunoenzymatic enzyme-linked immunosorbent assay (ELISA) commercial kits and were expressed in nanograms per milligram creatinine. Increased levels of MCP-1 and OPN were found in children with HN in comparison with study group 2 and controls (p < 0.05). UMCP-1/Cr correlated with half-time (T(1/2)) of the elimination phase of tracer excretion of technetium-99m-mercaptoacetyltriglycine ((99m)Tc-MAG-3) (p < 0.05).Receiver operator characteristic (ROC) analyses revealed good diagnostic profile for uMCP-1 only in identifying children (<40 %) with abnormal differential renal function (DRF) [area under the curve (AUC) 0.862], and in detecting kidney injury in all examined children (AUC 0.704).Additional studies with larger number of patients are required to confirm a potential application of uMCP-1 as a promising parameter for early identification of kidney obstruction.