The invention discloses a sensor for detecting a moving object, and the sensor is characterized in that the sensor comprises a microwave sensor and a supersonic distance sensor; the microwave sensor is disposed in a first installation ring; the supersonic distance sensor is disposed in a second installation ring; a side surface of the second installation ring is provided with a long groove; the interior of the long groove is provided with a rotating ring in a hinged manner; the interior of the rotating ring is provided with a connecting rod; the connecting rod can rotate relative to the rotating ring, and moves along the rotating ring axially; one end of the connecting rod is connected with a screw rod in the long groove; the other end of the connecting rod is in threaded connection with the second installation ring; the microwave sensor is in signal connection with the controller; the controller is in signal connection with the supersonic distance sensor; the microwave sensor sends a signal to the controller when the microwave sensor detects that the moving object enters a detection range, and the controller triggers the supersonic distance sensor to work. The sensor can achieve the precise detection of the object distance in a large range.