Introduction. Renal vein thrombosis (RVT) is one of the most common forms of neonatal thrombosis, accounting for 15-20% of systemic thromboembolism, which manifests at an average age of 2-3 days. Predisposing factors for RVT in newborns include: dehydration, sepsis, asphyxia, polycythemia, maternal diabetes, congenital defects of the renal vein, umbilical venous catheters. Material and methods. Description of a clinical case of RVT in the newborn based on the information collected from the medical sheet. Results. A 12 days-old baby girl, born on term, admitted in serious condition, with hematuria. On physical examination, the skin and mucous membranes were clean, normal in color. The abdomen was soft to palpation, in the right flank with signs of crepitation. Diuresis was 4.9 ml/kg/ hour. Laboratory examination showed leukocytosis with left deviation (WBC- 27.0x109/l, nonsegmented -19.0x109/l), thrombocytopenia -112x109/l, hematocrit -46, fibrinogen -2.89 g/l, prothrombin index -78%, ASAT -62.3 U/L, total protein - 51.0 g/l, serum creatinine -91 μmol/l, blood urea -5.4 mmol/l, proteinuria - 3.0 g/l, and gross hematuria (unchanged erythrocytes cover the field of view). On ultrasonography was found that the right kidney is enlarged-70x44mm, parenchyma 16 mm, irregular contur, increased echogenity. Renal angiography provided data for thrombosis of the inferior vena cava and right kidney with pathological changes characteristic for global renal infarction. The treatment included anticoagulants, correction of the fluid, electrolytes, and acid-base imbalance. Conclusion. Patients with RVT remain at higher risk of morbidity and/ or long-term mortality, including hypertension and chronic kidney disease(CKD), which requires monotorization and dynamic supervision to initiate early intervention and prevent complications.