The invention discloses a method and device for conducting hot air ignition through high-temperature waste flue gas. The high-temperature waste flue gas passes through a recovery air bellow, a first hot air pipeline, a dust collector, a second hot air pipeline, a draught fan and a third hot air pipeline in sequence, goes into an igniter and is mixed with air going in through a combustion-supporting air pipeline, ignited and burned. The high-temperature waste flue gas generated after combustion of a sintering machine are recovered and cyclically utilized through the recovery air bellow. According to the method and device, the high-temperature waste flue gas in a large flue is led back to the sintering igniter to serve as combustion-supporting air for ignition to replace part of normal-temperature combustion-supporting air. On one hand, pollutants in the waste flue gas can be decomposed through combustion reaction, and on the other hand, consumption of ignition gas is reduced through heat of the waste flue gas. Meanwhile, the total discharge amount of sintering waste flue gas is reduced.