Abstract: Force sensor for electric measuring of forces, mechanical stress or the like, which are converted in the interior of the force sensor into a mechanical normal stress field and then into an electric resistance change. Transverse to the normal stress .sigma..sub.j a piezo-resistive measuring element (17) consisting of at least one layer of resistance material is applied whose material constant c is selected such that a mechanical strain of the measuring element resulting from the strain of a carrier body (1) does not influence the measurement. The resistance layers may be overlying crossing patterns M.sub.1, M.sub.2 forming area elements (13) of equal area size which completely exhibits the mutually perpendicular strains .epsilon..sub.x, .epsilon..sub.y of the carrier body (1). For compensating disturbing influences exterior of the normal stress field a compensation element (18) is provided corresponding to the measuring element (17).