A torque detection apparatus includes a magnetic element that outputs a signal corresponding to a magnetic flux from a magnetic circuit including a magnetic yoke. The torque detection apparatus further includes a signal retrieval member electrically connected to the magnetic element, and a unit housing formed of resin and molded integrally with the magnetic element and the signal retrieval member so as to cover the magnetic element and the signal retrieval member. The unit housing includes a body portion provided with an internal space in which the magnetic yoke is housed, and a connector portion provided with an internal space in which an end of the signal retrieval member exposed from the resin is disposed. In the unit housing, a communication path is formed through which the internal space is in communication with the internal space.