Objective. To propose and introduce a diagnostic-treatment algorithm for the inferior vena cava (IVC) leiomyosarcoma into clinical practice. Materials and methods. During last 30 years in Zakarpattya Regional Clinical Hospital Named After Andriy Novak and Zakarpattya Antitumoral Centre were operated 8 patients, suffering the IVC leiomyosarcoma - 7 (87.5%) women and 1 (12.5%) man. Median of the patients' age have constituted 57 yrs old. For characterization of the affection localization in accordance to own views on the subject the classification of the IVC division into 7 segments was applied: infrarenal, іnterrenal, suprarenal, retrohepatic, іnfradiaphragmatic, supradiaphragmatic,іntracardial. Іntravasal localization of the tumor was observed in 3 (37.5%), extravasal - in 1 (12.5%), mixed - in 4 (50%) patients. In all the patients the open laparotomy approach was applied: in 1 (12.5%) patient median laparotomy was performed, and in 7 (87.5%) - bilateral subcostal laparotomy of a «Chevron» type. For the IVC alloprosthesis in 6 (75%) patients a politetrafluoroethylene prosthesis was applied, while in 2 (25%) - Gore-tex prosthesis of 18-22 mm in diameter. In 5 (62.5%) patients circular resection with the IVC alloprosthesis was done, in 2 (25%) - circular resection, the IVC alloprosthesis and іmplantation of right and left renal veins into the prosthesis, and in 1 (12.5%) - circular resection, alloprosthesis of IVC and implantation of left renal vein into prosthesis. Results. The operation median duration have constituted 215 (160 - 320) min, while the average volume of the blood loss - 305 (250 - 500) ml. The Degree II postoperative complications in accordance to classification of Clavien-Dindo were registered in 2 (25%) patients. Pulmonary thromboembolism, venous thrombosis, thrombosis of prosthesis, as well as intraoperative or immediate postoperative lethality were not observed. In 7 (87.5%) patients a radical intervention was performed. In 3 (37.5%) patients a remote hepatic and pulmonary metastases have been developed, leading to their death in terms from 10 to 34 mo. General one-, two- and a three-ear survival have constituted 87.5, 75 and 62.5%, accordingly. Conclusion. Surgical approach of a «Chevron» type and the staged dissection of IVC guarantees an adequate visualization of its іnfra-, іnter- and suprarenal segments. The «piggyback» procedure of hepatic mobilization and Pringle maneuver constitute necessary parts on the stage of dissection in retrohepatic, infradiaphragmatic and supradiaphragmatic segments of IVC. Radical tumoral excision with the IVC prosthesis and implantation, when needed, of renal or hepatic veins - is the only one possibility for improvement of the patients' quality of life in the IVC leiomyosarcoma.