The invention discloses a garbage disposal device capable of utilizing self-circulation pyrolysis gas for preheating air. The device comprises a feeding opening, a garbage pyrolysis furnace wall, a first horizontal heat conduction plate, a vertical heat conduction plate, a first smoke circular pipeline, a top smoke circular pipeline connection opening, a tail gas pipeline connection opening, a second horizontal heat conduction plate, a second smoke circular pipeline, a first induced draft fan, an air preheating cavity connection opening, a first air inlet, a garbage pyrolysis furnace, an air preheating cavity, an exhaust opening, a horizontal air distribution pipeline, a tail gas treatment pipeline, a bottom smoke circular pipeline connection opening, a second induced draft fan, an observation window, a vertical air distribution pipeline, a settling pond, a tail gas purification device, an air distribution system, a smoke circular system and other structures. According to the disposal device, the reduction reaction efficiency is improved, the garbage heat treatment efficiency is ensured; and meanwhile, the self-circulation pyrolysis gas can be used for preheating the air, it can be ensured that low-heat-value components such as aromatic alcohol and heavy oil can be sufficiently decomposed in the reaction, and pollutant emissions in the tail gas can be reduced.