The invention belongs to the field of oil sludge disposal and repairing of serious organic pollutant soil, and relates to a smoldering reaction device. The smoldering reaction device comprises an airinlet device, a heating device and a reinforced fireproof wall body, a tail gas collecting device and a loading and unloading push-pull door, wherein the reinforced fireproof wall body is provided with the loading and unloading push-pull door; the reinforced fireproof wall body is surrounded into a space structure with a rectangular cross section; the tail gas collecting device and the heating device are arranged on the top and the bottom of the space structure surrounded by the reinforced refractory wall body respectively; the tail gas collecting device, the reinforced fireproof wall body andthe heating device form a smoldering reaction cavity together; and the air inlet device is arranged on the reinforced smoldering wall body and communicates with the heating device. According to the smoldering reaction device, the cost of a smoldering reactor can be lowered, the service life of the smoldering reactor can be prolonged, and the smooth start of the smoldering can be ensured.