A sealing element for sealing a strand-shaped body in an aperture of a wall, in particular for sealing a loom of cables in an aperture of a vehicle-body sheet, has a bush through which the strand-shaped body is guided. The bush has a circumferential wall bounding a cavity. A clamping element for clamping the bush against the aperture reaches with an extension into the cavity. The extension and/or the cavity are of a conical configuration such that, during clamping with the clamping element, the extension is pressed into the cavity, and therefore the circumferential wall is clamped radially against the aperture in the region of the conical configuration.