Two -layer double reheat boiler gas recirculation system that arranges under in flue gas spout relates to a double reheat boiler gas recirculation system. The utility model provides an unit operationfeedback exist the momentum too big, influence flow field form in the stove, destruction primary zone flow field, problem that adjustable nargin is little. Furnace's four corners incline is vertical under the boiler is provided with one and is listed as the burner nozzle, furnace's the four corners incline outside all is provided with the gas recirculation flue near the bottom under the boiler, every gas recirculation flue falls into two air inflow branch, air inflow branch's exit is provided with recirculated flue gas nozzle more respectively, again on recirculated flue gas nozzle install furnace's under the boiler the four corners incline, and one again the recirculated flue gas nozzle be in the intermediate position of burner nozzle, another again the recirculated flue gas nozzle be inthe below of burner nozzle. The utility model discloses realize adjusting more effectively reheat steam temperature, it is poor also can to reduce the flue gas lateral deviation simultaneously, improves double reheat boiler two -stage high -temperature reheater's operating condition.