The invention relates to a hydro-mechanical gearbox with a hydraulic pump, a hydraulic motor and a set of planetary gears, whereby the pressure line of the hydraulic pump is conducted back, via the inserted hydraulic motor, to the suction line of the hydraulic pump, thereby forming a circuit, and whereby either the sun wheel or the planet-carrier of the set of planetary gears is coupled in a rotationally fixed manner to the driven shaft of the gearbox, and the other one of these two elements of the planetary gear is coupled in the same manner to the output shaft of the gearbox, and the hollow wheel is coupled to a rotational unit of the hydraulic pump, preferably to its casing, while the other rotational unit of the hydraulic pump is coupled to the frame or to the output shaft of the gearbox; according to the invention one rotational unit of the hydraulic motor, preferably its rotor, is coupled in a rotationally fixed manner to the driven shaft of the gearbox, and the other unit of the hydraulic motor, preferably its static part, is coupled either to the frame/housing of the gearbox or to its output shaft.