The invention discloses a garbage pyrolysis gasification furnace, the structure of which comprises an inlet, a pyrolysis furnace, a gas outlet pipe, a turning mechanism, a steam inlet, and a burner. Embedded with an air outlet pipe, the plastic waste inside the turning mechanism is pyrolyzed, and the plastic waste in the middle is moved upward through the structure of the plate body, and at the same time, the melted plastic waste in the middle is flowed downward through the inlet and flow ports, and the upward flow is carried out. The middle and lower flow circulates, and at the same time, through the sliding of the sliding plate, the flow tube inside the supporting plate makes the molten garbage in the middle flow down, avoiding the carbonization of the external plastic garbage in the first step, and the steam is transmitted through the transmission tube, to the center The molten plastic waste inside is pyrolyzed, and at the same time, after the expansion body is heated and expanded, the connecting rod protrudes from the inside of the hollow ball, increasing the contact surface with the melted plastic waste, thereby ensuring that the plastic in the center is decomposed.