A measuring apparatus for measuring forces acting upon a bearing, particularly the radial forces, effective at a roller bearing. The measuring apparatus essentially comprises two rings, typically formed of metal, which are concentrically interconnected by means of a web. The roller bearing transmits the force to be measured to one of the rings, whereas the other ring is fixed. The one ring rocks or moves in relation to the fixed ring and the deformation prevailing at the web is electrically measured and indicated in a display or indicator device. The measuring apparatus serves for measuring the tension in belts, bands, and the like.