The invention provides a coupling detection device. The coupling detection device comprises a coupling detection device body, a detection part and a warning device. The warning device is electrically connected with the detection part. An upper flange is arranged at the upper end of the coupling detection device body. A lower flange is arranged at the lower end of the coupling detection device body. The detection part is an acoustic detection part and comprises an upper acoustic wave emitter, a lower acoustic wave emitter, an acoustic wave receiving device and a data processor. The upper acoustic wave emitter and the lower acoustic wave emitter are located on the same side of the coupling detection device body. The acoustic wave receiving device is located on the other side of the coupling detection device body. The central axis of the acoustic wave receiving device is located in the position between the upper acoustic wave emitter and the lower acoustic wave emitter. The upper acoustic wave emitter, the lower acoustic wave emitter and the acoustic wave receiving device are fixedly connected with the coupling detection device body. The data processor is electrically connected with the acoustic wave receiving device. The warning device is provided with a Bluetooth alarm. According to the coupling detection device, coupling detection is high in accuracy rate and small in error.