Renal tumors account for 2 to 3 % of all malignant tumors in adults. Of all patients with renal cell carcinoma, 30 to 40 % have advanced forms of the disease. In the literature, the term "giant renal tumor" is used for tumors larger than 20 cm. In this article, we report a case of surgical treatment for a giant malignant kidney tumor.Patient N., female, 54 years old, referred to an outpatient clinic with complaints of a change in the shape of the abdomen on the left with a palpable large tumor, abdominal pain, shortness of breath, weakness, constipation, episodes of blood in the urine and increased blood pressure. Body mass index 30.2 kg/m2. Ultrasound examination revealed a large tumor in the left retroperitoneal space. Laboratory testing of blood, urine was performed, findings were unremarkable. According to the data of magnetic resonance imaging, the left kidney was transformed into a large cystic solid formation, measuring 30.5 х 17.5 х 17.0 cm, heterogeneously accumulating a contrast agent with a solid component. Patient was admitted to the urology department for surgical treatment. We performed radical nephrectomy on the left with thoracolumbar laparotomy access on the left with resection of the 10th rib, resecting the renal tumor with the adrenal gland, total weight of the complex was 10.7 kg. The histological structure was determined as poorly differentiated renal carcinoma with invasion of the perinephric tissue. In the adrenal gland, fields of fresh erythrocytes with an admixture of tumor tissue were noted. Examined lymph node tissue was completely replaced by tumor cells. Postoperative period was characterized by episodes of dynamic intestinal obstruction. The patient was discharged from the department in a satisfactory condition on the 13th day after the operation, but died 1.5 months after discharge, the cause of death has not been established, as no autopsy was performed. Thus, the size of the tumor is not a contraindication to surgical treatment, which improves the survival rate of patients with malignant renal tumors.