FIELD: mechanical engineering. SUBSTANCE: hydrostatic screw-nut transmission consists of a hydraulic tank, throttles, a reversible gear hydraulic pump and an overflow valve, a screw with an external trapezoidal thread and a female nut with a similar female thread, on the side surfaces of which there are pockets connected through the throttles to the oil supply channel from the pump, and the diametral surfaces of which are made with holes connected to the oil drain channel into the hydraulic tank, equipped with an adjustable additional throttle included in the oil drain channel. The transmission is also equipped with an adjustable mechanical variator, the input of which is kinematically connected to the screw, and the output is connected to the input shaft of the hydraulic pump. EFFECT: extended transmission fine tuning range and improved accuracy and reliability. 1 cl, 2 dwg.