The invention discloses a flue gas purification device for a spray quenching vehicle. The technical scheme includes that a garbage disposal combustion chamber is arranged in a carriage, the flue gas purification device comprises a water tank, a flue gas fan, a coiled pipe, a quenching water pump, a spray water pump and a chimney, the inside of the water tank is divided into an independent spray section and a quenching section by a partition, the coiled pipe is positioned in the combustion chamber of a garbage disposal device, two ends of a second flue gas guide pipe are connected with the combustion chamber of the garbage disposal device and the spray section of the water tank respectively, two ends of a first flue gas guide pipe are connected with one end of the coiled pipe and the spray section of the water tank respectively, two ends of a third flue gas guide pipe are connected with the other end of the coiled pipe and the quenching section of the water tank respectively, the chimney is connected with the quenching section of the water tank, and the flue gas fan, the spray water pump and the quenching water pump are fixed on the left side wall and the right side wall of the outside of the water tank through supports respectively. The flue gas purification device is simple in structure and small in size, can be assembled on a motor vehicle, and is used for purifying flue gas generated by the garbage disposal device for the vehicle.