The invention relates to a hazardous waste activated carbon green regeneration upgrading system, which comprises a desorption carbon tank, a high-temperature plasma device, a variable-frequency heater, a catalytic oxidation box, a carbon activation furnace and a gas-gas heat exchanger, an inlet of the desorption carbon tank is communicated with a nitrogen pipeline, and an outlet of the desorption carbon tank is connected with the high-temperature plasma device, the carbon activation furnace and the catalytic oxidation box, the outlet end of the high-temperature plasma device is sequentially connected with a first gas-gas heat exchanger and a second gas-gas heat exchanger. The hazardous waste activated carbon green regeneration upgrading system and method can be widely applied to sewage treatment plants, coking wastewater plants, chemical plants, pharmaceutical factories, pesticide factories and fine chemical factories, effectively fill the blank in the field in China, are green and environmentally friendly, and are suitable for popularization and application in the field of environmental protection.