A differential gearing unit with controllable torque and rotational speed distribution, composed of a housing (1), a differential gearing (6), a superposition gearing (7) and an auxiliary drive (8), with the differential gearing (6) comprising an input member (11) which is driven by the vehicle engine, and two output members (15, 16) with output shafts (3, 4), and with the superposition gearing (7) being a planetary gear set which is connected to two members (15, 16) of the differential gearing (6) and to the auxiliary drive (8). In order to provide precise control with a low-power auxiliary drive, the superposition gearing (7) comprises a first (22) and a second (27) sun gear, a first (20) and a second (25) ring gear and first (21) and second (26) planet gears on a common planet carrier (28), with the first (21) and second (26) planet gears meshing in each case with the first (22) and second sun gear (27) respectively and with the first (20) and second ring gear (25) respectively, and with a ring gear being rotationally fixedly connected to an output shaft.