The invention relates to a push type feeding biomass gasification furnace pyrolysis tube device, and is characterized in that the invention comprises a heating gas inlet (1), a jacket external tube (2), a pyrolysis tube (3), a box heat exchanger (4), a spiral fin (5), a box heat exchanger flow clapboard (6) and a gas outlet (7), wherein, the heating gas inlet (1) and the gas outlet (7) are respectively welded to the upper and lower sides of the right and left ends of the jacket external tube (2); the pyrolysis tube (3) is concentrically embedded into the jacket external tube (2) every end of which is connected with every end of the pyrolysis tube (3) in the way of sealing and welding by the annular plate. Compared with that only pyrolysis tube is adopted, the invention greatly reduces thedistance from the transmission process of the biomass material to the heating surface, and leads the pyrolysis of the material to be fuller, thus improving the oxidation and gasification process of the lower part.