The invention discloses a fast pyrolysis device for domestic garbage. The fast pyrolysis device for the domestic garbage comprises a rotating shaft, a pyrolysis chamber and a flue gas chamber, whereina spiral blade is welded on the rotating shaft and used for carrying garbage to move, a scraping rod is welded on the spiral blade, the pyrolysis chamber is used for thermally decomposing the garbage, the pyrolysis chamber is arranged outside the rotating shaft in a sleeving mode and coaxially arranged with the rotating shaft, the upper side of one end of the pyrolysis chamber is provided with apyrolysis gas outlet and a garbage inlet, the flue gas chamber is used for heating the pyrolysis chamber, the flue gas chamber is arranged outside the pyrolysis chamber in a sleeving mode and coaxially arranged with the pyrolysis chamber, and one end, close to a pyrolysis residual carbon outlet, of the flue gas chamber is provided with a flue gas inlet. According to the fast pyrolysis device for the domestic garbage, the pyrolysis chamber and the flue gas chamber are coaxially fixed and separated from each other, pyrolysis gas and high-temperature flue gas are completely isolated, the thermalvalue of the pyrolysis gas is high, the pyrolysis gas is in countercurrent contact with the garbage, tar generated by high-temperature pyrolysis stays on solid garbage, carbonization occurs along withgradual pyrolysis of the garbage, the tar stays in the residual carbon, and the tar content in the pyrolysis gas is low.