The invention discloses a steam reforming gas purification system and technique for radioactive organic waste. The system comprises a fluidized bed, wherein an outlet of the fluidized bed communicateswith a cyclone separator through a pipeline; the cyclone separator communicates with a high-temperature filter; the cyclone separator and the high-temperature filter communicate with a solid waste collector; the high-temperature filter communicates with a full oxidizing furnace, a spray tower and a gas-liquid separator in sequence; a spray nozzle for alkaline washing is arranged in the spray tower; the gas-liquid separator communicates with a vacuum pump and a chimney in sequence; the cyclone separator communicates with the solid waste collector through a first solid waste collecting pipe; the high-temperature filter communicates with the solid waste collector through a second solid waste collecting pipe; the gas-liquid separator enables the liquid to flow to the spray tower through a second liquid waste collecting pipe; and the spray tower recycles the liquid through a first liquid waste collecting pipe.