The invention discloses a metering box unlocking power supply device comprising an unlocking housing, a fuse box, a sleeve 1, a sleeve 2, an insert bar 2, a fixed member, an insert bar 1, an insert block, an unlocking switch, a battery and a mobile housing; the metering box is simple and reasonable in structure, low in production cost, easy to mount, and an open-to-break grounding device is arranged; the box door is opened so as to cut off the power of the metering box device, i.e., when the box door is open, a conductive wire board moves rightward under a spring1 effect and is separated froman input wiring board and an output wiring board, thus disconnecting the input wiring board from the input wiring board; in addition, the box device can be earthed, i.e., under the spring 1effect, a grounding connecting board moves rightwards so as to connect a ground joint 1 with a ground joint 2, thus ensuring the metering box device to timely ground, and improving maintenance personnel safety in maintenance.