The present invention discloses a high-density electrical method instrument electrode converter detection device. The device comprises a high-density electrical method instrument host, a multi-channel electrode converter and a detector; the high-density electrical method instrument host includes a first transceiver, a first microcontroller, an input module and a display module which are connected in order; the multi-channel electrode converter includes a second transceiver, a second microcontroller, a decoder module and a first relay module which are connected in order, the second microcontroller is connected with a first communication module, and the first communication module is provided with at least one cable access; and the detector includes a cable joint, a cable state switcher and a plurality of state joints which are connected in order, and the cable state switcher includes a second communication module, a third microcontroller and a second relay which are connected in order. The high-density electrical method instrument electrode converter detection device can detect the work state of any relay of the multi-channel electrode converter in time, can directly display the work states of all the relays on a host screen, and is simple in structure, small in size and not easy to damage so as to improve the efficiency of the yield work.