A sensor configured to detect displacement of a rotation angle of a shaft due to a rotation or a turn of the shaft, the sensor includes: a bearing rotatably supporting the shaft; and a housing including a bearing hole to which the bearing is fixed. The shaft and an inner circumferential surface of the bearing are fixed to each other by an adhesive agent, and an outer circumferential surface of the bearing and an inner circumferential surface of the bearing hole of the housing are fixed to each other by an adhesive agent.