A torque sensor includes: a torsion bar; a multi-pole magnet; a pair of yokes on an outside of the multi-pole magnet in a radial direction and providing a magnetic circuit in a magnetic field generated by the multi-pole magnet; and a pair of magnetic sensors arranged along a circumferential direction. Each magnetic sensor includes a magnetism sensing part for detecting a magnetic flux density generated in the magnetic circuit, and outputs a detection signal to an external computing device. The magnetic sensors output the detection signals to the external computing device such that the computing device calculates a sum of outputs or a difference of outputs of the magnetic sensors so as to cancel a variation of the outputs produced by a magnetic flux generated from the multi-pole magnet and directly reaching the magnetism sensing parts.