The invention provides an automatic intelligent line checking device for an intelligent substation, and belongs to the field of measurement. The automatic intelligent line checking device is provided with two testing sockets, wherein n+2 relays are arranged on a first testing socket; n-1 resistor matrixes are arranged on a second testing socket; prefabricated cable plugs at the two ends of a cable to be tested are correspondingly inserted into the two testing sockets; a control unit is used for establishing the mapping relation between the resistor matrixes and the prefabricated cable plugs, respectively controlling a contact of each relay to be connected and disconnected in sequence and detecting the resistance value between core line loops of each cable to be tested; the control unit is capable of judging the connection and disconnection condition between the core lines at the two ends of the cable to be tested by controlling the connection and disconnection of each relay contact and detecting the level fluctuation of each relay port; and the control unit is capable of discriminating the connection sequence of the core lines of the cable to be tested on the prefabricated cable plugs by diodes, thereby solving the problem of intersecting wiring of the cable. The automatic intelligent line checking device can be widely applied to the design and manufacturing fields of cable testing devices.