The utility model relates to a biomass fluidization gasification furnace which is suitable for biomass gasification. The utility model is composed of a feeder, a gasification furnace body and an insulated jacket, wherein the gasification furnace body is arranged in the insulated jacket; the feeder is connected with the lower part of the gasification furnace body; a corrugated expansion joint is arranged on the gasification furnace body. Because the utility model adopts a corrugated expansion joint, the efficient deformation for the contraction generated by the gasification furnace body caused by the hot and cold change can be provided, which causes that one effective buffer is established between the furnace body of a metal gasification furnace and the constraint of the outside pipeline; the utility model can ensure the free extension of the furnace body following with temperature change; the utility model can avoid the local deformation of the furnace body; the service life of the utility model can be extended; the utility model is suitable for hot and cold environmental change.