Epithelial-mesenchymal transition (EMT) is a process in which epithelial cells may express mesenchymal cell markers with subsequent change in their functions, and it may be part of the etiopathogenesis of kidney disease.The aim of this study was to evaluate the immunexpression of some EMT inducers and markers in frequent nephropathies in pediatric patients.59 patients aged 2-18 years old were selected and divided into 6 groups of frequent nephropathies in children and adolescents, as well as one control group. Urea and creatinine data of the patients were recorded. TGF-β3, fibronectin, α-SMA and vimentin were evaluated by immunohistochemistry.Glomerular TGF-β3 was higher in the Lupus Nephritis and Acute Diffuse Glomerulonephritis (ADGN) groups than in the control group. Glomerular fibronectin was higher in the Podocytopathy, Lupus Nephritis, ADGN and Membranous Glomerulopathy patients than in control subjects. The expression of α-SMA was higher in the tubulointerstitial compartment of ADGN and Membranous Glomerulopathy groups than in the control group. Glomerular α-SMA was higher in ADGN patients than in control and Berger's Disease groups. Glomerular vimentin was higher in individuals with ADGN than in those with Podocytopathy, Lupus Nephritis, Berger's Disease and Thin Basement Membrane Disease/Alport Syndrome. There was a positive correlation between fibronectin in the tubulointerstitial compartment and creatinine levels, between α-SMA and vimentin in both tubulointerstitial and glomerular compartments, and between urea and creatinine levels of patients, regardless of their nephropathy (p<0.05 for all results).These markers may possibly be used as indicators of renal functional impairment in various nephropathies in pediatric patients.