An electromechanical steering system for a motor vehicle, comprising a steering pinion which is connected to a second partial shaft and which is in engagement with a rack for steering wheels, wherein the rack is mounted such that it can be displaced along a longitudinal axis in a third housing, at least one electric motor for steering force assistance, a torque sensor unit, which is arranged between a first partial shaft connected to the steering wheel and the second partial shaft and detects a torque introduced into the steering wheel by the driver, wherein a steering column comprising the first partial shaft and the second partial shaft is telescopic and has an outer casing tube and an inner casing tube, the torque sensor unit comprising: - a ring magnet which can be connected to the first partial shaft in a torque-proof manner, - at least one magnetic yoke which can be connected to a second partial shaft and which is arranged in a magnetic field originating from the ring magnet, and - at least two magnetic flux conductors which can be connected to the second partial shaft and which conduct the magnetic fluxes generated by the at least one magnetic yoke, - a sensor unit having a first housing, which detects a change in rotational angle between the partial shafts by measuring the magnetic flux density generated between the magnetic flux conductors, - a second housing, which surrounds the ring magnet, the at least one magnetic yoke, the at least two magnetic flux conductors and the sensor unit and which has a housing opening which is at least partly closed by a housing cover, characterized in that the second housing and the housing cover are made of a magnetically conductive material for the magnetic shielding of the torque sensor unit, and in that the housing cover has a cutout, through which the first partial shaft passes when installed and in which an inner casing tube is accommodated, wherein the inner casing tube is made of a magnetically conductive material for the magnetic shielding of the torque sensor unit. - a ring magnet which can be connected to the first partial shaft in a torque-proof manner, - at least one magnetic yoke which can be connected to a second partial shaft and which is arranged in a magnetic field originating from the ring magnet, and - at least two magnetic flux conductors which can be connected to the second partial shaft and which conduct the magnetic fluxes generated by the at least one magnetic yoke, - a sensor unit having a first housing, which detects a change in rotational angle between the partial shafts by measuring the magnetic flux density generated between the magnetic flux conductors, - a second housing, which surrounds the ring magnet, the at least one magnetic yoke, the at least two magnetic flux conductors and the sensor unit and which has a housing opening which is at least partly closed by a housing cover, characterized in that the second housing and the housing cover are made of a magnetically conductive material for the magnetic shielding of the torque sensor unit, and in that the housing cover has a cutout, through which the first partial shaft passes when installed and in which an inner casing tube is accommodated, wherein the inner casing tube is made of a magnetically conductive material for the magnetic shielding of the torque sensor unit.