The invention discloses a gas-insulated power supply device. The gas-insulated power supply device comprises a high-transformation-ratio transformer, a voltage regulating circuit for achieving regulation of output voltage of the high-transformation-ratio transformer, a protection-level current transformer, a metering-level current transformer and a control screen unit, wherein the high-transformation-ratio transformer is connected with a high-voltage power transmission line through a high-voltage bushing and is connected with an external electrical load through a power output terminal, the first end of the protection-level current transformer is connected to the high-voltage bushing, the second end of the protection-level current transformer is connected to a high-voltage protection control module of the control screen unit, the first end of the metering-level current transformer is connected to the high-voltage bushing, the second end of the metering-level current transformer is connected to an electric energy metering module of the control screen unit, the control screen unit comprises the high-voltage protection control module, the electric energy metering module, a fault recording module, a low-voltage control module and a power module, and a power supply port connected to the high-transformation-ratio transformer is used for providing power for the high-voltage protectioncontrol module, the electric energy metering module, the fault recording module and the low-voltage control module.