Fiber Bragg grating strain sensors have the problem of cross-influence between temperature and strain during measurement, and temperature has a significant impact on stress measurement results. To obtain accurate stress measurement results, it is necessary to significantly reduce or eliminate the impact of temperature. Currently, the reference grating method or temperature measurement coefficient correction method is difficult to obtain ideal results. This paper proposes to use a cross-sectionally symmetrical cantilever beam structure as a sensitive element, using the principle of opposite strain and temperature change on the upper and lower surfaces of the cantilever beam, and symmetrically pasting two fiber Bragg gratings on the upper and lower surfaces of the cantilever beam, using the result difference to eliminate the temperature effect and improve the measurement sensitivity. This paper studies the sensing performance of this new type of temperature self-compensated fiber Bragg grating strain sensor, and installs this type of sensor on the anchor of the cable for cable force measurement. The research results show that the developed fiber Bragg grating strain sensor can significantly reduce the impact of temperature and achieve the purpose of temperature self-compensation; using this type of sensor for cable force measurement has high accuracy and sensitivity, which can meet the practical needs of engineering applications.