To easily and quickly mount a torque sensor to a torque transmission means, and to reduce costs.

In torque sensor-mounting structure for steering, a torque sensor 2 is mounted to a shaft (torque transmission means) 1 for transmitting torque for steering from a handle side to a steering wheel side, the torque sensor 2 is interlocked to the torque transmission means 1 by fitting a spline shaft 3 (grooved shaft) with a plurality of grooves being extended in an axial direction to a spline hole (grooved hole) 4, and an adhesive is filled between the grooved shaft 3 and the grooved hole 4 for hardening.