The utility model relates to a direct-current faulty insulator detection electrode and a device. The device comprises a measuring unit and a data-receiving unit; wherein, one direct-current electrode of the measuring unit is provided with a built-in measuring circuit; an infrared signal transmission channel is arranged between the data-receiving unit and the built-in measuring circuit of the direct-current electrode; two direct-current electrodes are respectively fixed on connectors adopted by the measuring unit; a gap is reserved between the two direct-current electrodes; the connectors are respectively mounted on both ends of an insulator support; and probes are mounted on the connectors. The shells of the direct-current electrodes with the built-in measuring circuits are hollow cylindrical aluminum boxes, and the center of the bottom of each hollow cylindrical aluminum box, which is close to the direct-current electrode, is provided with a round hole, in which movable metal blades and fixed metal blades are mounted. The utility model has the following advantages: the structure is simple, the design is novel, the utility model can overhaul and detect the insulators of a direct-current transmission line without interrupting power supply, and the insulators of a direct-current transmission line of positive or negative 500kV can be detected with power on, so that faulty insulators can be found and replaced in time in order to ensure the safe and reliable operation of the direct-current transmission line and prevent the occurrence of pollution flashover.