The invention discloses a device and a method for indirect thermal desorption disposal of persistent organic pollutant contaminated soil. The device comprises a contaminated soil pretreatment system, a feeding system, a thermal desorption system, a discharging system, a tail gas purification system and an automatic control system, wherein the contaminated soil pretreatment system is connected with a feed opening of the thermal desorption system through the feeding system, a solid discharge opening of the thermal desorption system is connected with the discharging system, and a gas discharge opening of the thermal desorption system is connected with an inlet of the tail gas purification system. According to the method, after pretreatment, contaminated soil is conveyed to the thermal desorption system for desorption for 10-40 min at the temperature of 400-600 DEG C, and desorption exhaust gas adopts a technology including procedures of cyclone dust removal, two stages of spraying, drying and activated carbon adsorption / gliding arc degradation. The device and the method adopt indirect heating, so that risks of generation of poisonous materials such as dioxine and the like are avoided effectively; and a double-layer cylinder rotary kiln type furnace body, the furnace body axis and the ground form a 0-degree angle, and accordingly, the operation and maintenance costs are reduced.