The utility model discloses a hierarchical recovery system of heat adjustable flue gas waste heat, characterized by: to being in the afterbody flue between boiler economizer and the dust remover, heat adjustable residual heat from flue gas system arranges, cut apart to become the regional flue gas passageway of regional flue gas passageway in left side and right side with the afterbody flue by vertical septum, nearly boiler furnace one side is depended on to the regional flue gas passageway in left side, arranges air heater in the regional flue gas passageway in left side, and in the regional flue gas passageway in right side, the upper portion that is in the regional flue gas passageway in right side sets up high temperature cigarette water heat exchanger, and the lower part that is in the regional flue gas passageway in right side sets up low temperature cigarette water heat exchanger, realizes grading of low -level (stack -gas) economizer cigarette water heat exchanger and arranges, top at the regional flue gas passageway in right side sets up adjustable baffle. The utility model discloses can improve recycling flue gas waste heat and rate, increase the energy -conserving effect of low -level (stack -gas) economizer, operation of improvement equipment and regulation.