Congenital nephrotic syndrome (CNS) is an inherited disease that is caused by gene mutations and is inherited by an autosomal-recessive mechanism. In most cases, it is associated with genetically mediated defects in the components of the glomerular filtration barrier, especially nephrine and podocytes, with a typical histological picture of diffuse mesenteric sclerosis or focal-segmental glomerulosclerosis. According to genetic research, the primary CNS caused by gene mutations in one of the five genes (NPHS1, NPHS2, WT1, LAMB2, PLCE1) or chromosomal abnormalities. Secondary CNS is combined with other diseases of systemic or renal origin. The onset of the disease manifestation is possible in the antenatal period or during the first three months of life. CNS is manifested by significant hypoproteinemia, proteinuria and diffuse edema. Treatment of congenital nephrotic syndrome is mainly symptomatic therapy, such as: control of edema, azotemia, thyroid function, prevention and treatment of secondary complications (infections and thrombosis). Molecular genetic testing is the «gold» standard for genotyping of this disease. The course of СNS is unfavorable due to the rapid development of end3stage chronic renal failure. The purpose of article is to expand the knowledge of pediatricians and neonatologists about the clinical, laboratory, instrumental and pathomorphological features of Finnish type of СNS in the neonatal age. Clinical case. The article presents clinical, laboratory, instrumental, pathomorphological and molecular-genetic features of the Finnish type of CNS with the manifestation in the early neonatal period. Conclusions. The example of this case shows the necessity of a comprehensive approach at the examination of children suffered from CNS to verify the type of disease, determine the prognosis and treatment tactics. The research was carried out in accordance with the principles of the Helsinki declaration. The informed consent of the patient was obtained for conducting the studies. No conflict of interest was declared by the authors. Key words: congenital nephrotic syndrome, newborn, molecular genetic testing.