The utility model provides a boiler discharge fume full heat recovery of direct contact with white device disappears, belongs to boiler heat supply and energy utilization technology field, and this system includes three heat exchange module, and the low temperature section of wherein discharging fume sprays hot recoverable module and is reduced boiler low temperature section exhaust gas temperature to 20~30 DEG C of back emissions through the mode of spraying by intermediary's circulating water to recovery discharge fume waste heat and condensate water, and " it is white to disappear " of realizing the flue gas, and the surplus enthalpy exchanger heating new trend sprayed circulation water of intermediary's circulating water rethread, boiler air inlet heating humidification module sprays the heating humidification by the new trend sprayed circulation water after heating up to the boiler air inlet, and furnace is sent into through the boiler air intake to the high wet air inlet of furnace to the waste heat of will discharging fume experiences in the furnace combustion processes again with the vapor form and transfers to during the boiler discharges fume, it discharges fume then through discharging fume high temperature section waste heat recovery module by heated water recovery waste heats such as heat supply network return water to have shown the boiler that has improved the water capacity to the recycle of discharge fume waste heat and condensate water has been realized.