The invention provides a corrosion-resistant flue gas heat transfer interface temperature controllable and adjustable waste heat recycling device. The corrosion-resistant flue gas heat transfer interface temperature controllable and adjustable waste heat recycling device is provided with a heat exchanger, a steam-liquid mixed heater, a steam-liquid separation tank, a controller for adjusting and controlling the flue gas waste heat of a boiler and the like; a way for heating by directly mixing steam and cold water is adopted to reduce heat loss; the controller is introduced; a temperature reference value is used as a control reference value; and compared with an acid dew point, the corrosion-resistant flue gas heat transfer interface temperature controllable and adjustable waste heat recycling device has the advantages that the ratio of the mixed steam to external water is regulated, so that the temperature of water returning to the heat exchanger is adjusted, the lowest wall temperature of a flue gas waste heat recycling device can be stably controlled to be higher than the acid dew point no matter how the load of the boiler changes, and meanwhile the heat of flue gas generated by the boiler is recycled to the maximum extent.