The invention discloses a hot air heat utilization system for an indirect cooling tower. The hot air heat utilization system comprises the indirect cooling tower and an air inlet header; a plurality of air outlets are symmetrically formed in the part above a heat exchange area of the indirect cooling tower, and an annular air extracting box is arranged outside the air outlets and is connected to the outer side of the indirect cooling tower in a sealed mode; an outlet of the annular air extracting box is connected to the air inlet header, and hot air of the indirect cooling tower is conveyed into an air heater by a fan for being heated again after flowing through the air inlet header. According to the hot air heat utilization system, during the low-temperature operation period of a unit, the hot air of the indirect cooling tower is utilized as the air source entering the air heater, and therefore the steam extraction amount of the air heater can be lowered, the operation efficiency of a steam turbine can be improved, the exhaust gas temperature of a boiler can be increased, and blockage and corrosion of an air pre-heater can be reduced; the air extracting box is arranged in an annular mode, and therefore air inletting is stable; during the low-temperature operation period, the coal consumption of power generation can be lowered by 0.5 g/(Kw.h).