The invention provides a device for detecting a relative position of a quenching sensor and a rotary supporting raceway, belonging to the technical field of industrial measurement. The device mainly comprises a ruby probe, a pressure sensor, a flange, a transformer bracket, a servo motor, a ball screw, a screw nut, an upright post, a control system, a guide rail, a supporting seat, a base, a sliding plate, and the like. In the device, the ruby probe is used for inducing, the pressure sensor is used for feedback, and the control system is used for displaying and adjusting the relative positionof the quenching sensor and the rotary supporting raceway. The detection device provided by the invention has simple structure and convenient use, is used for automatically detecting the relative position of the quenching sensor and the raceway, can effectively lighten the labor intensity of workers, acutely ensure the depth and the evenness of a quenching layer, improve the quality of the quenching layer on the raceway surface and the use performance of a rotary support.