The invention relates to a self-supplying current measuring device, comprising a current signal sampling-processing device and a current signal receiving-displaying device, wherein the current signal sampling-processing device comprises a Hall current sensor unit, a micro-controlled processor and a Zigbee sending module; the micro-controlled processor is respectively connected with the Hall current sensor unit and the Zigbee sending module; the current signal receiving-displaying device comprises a Zigbee receiving module, a single chip microcomputer and a display screen; the input pin and the output pin of the single chip microcomputer are respectively connected with the Zigbee receiving module and the display screen; the Zigbee receiving module is connected with the Zigbee sending module through a wireless channel. The self-supplying current measuring device is simple in structure, can quickly and precisely detect the current in lead wires, and can display the current in number form by the display screen, so that the efficiency of power grid current detection is improved.