To detect both left and right steering torques inputted to a steering wheel by a single detection part, in a steering torque detector for a cable type steering device.

Pressing parts 19a, 19a arranged in the middle of an arm member 19 are brought into contact with magnetostrictive materials 25L, 25R respectively arranged on the inside of a pair of coils 24L, 24R, and reaction forces of outer tubes 6o, 7o of a Bowden cable, to which an axial compression force works by steering torque, and an initial load of a Belleville spring 17 are applied to both ends of the arm member 19. The loads applied to both magnetostrictive materials 25L, 25R are varied according to the steering torque even when the direction of steering torque inputted to the steering wheel is changed and the working point of the reaction force of the axial directional compression force of the outer tubes 6o, 7o is switched from one end to the other end of the arm member 19, and consequently, the steering torque can be detected by means of either of the magnetostrictive materials 25L, 25R alone.