The invention belongs to the field of a flue gas monitoring and testing device, and particularly relates to an analog flue gas mixing device based on a high temperature humidity generator. The analog flue gas mixing device based on the high temperature humidity generator comprises a gas tank (2), a standard-gas flow meter (7), a moisture flow meter (8), a foam generator (10), a constant temperature water tank (11), a dry gas flow meter (15), a T-junction (16), a mixed moisture flow meter (17), a small testing case (20), a medium testing case (21), a mixed moisture pipeline (23), a standard-gas heating pipeline (24), a mixing gas tank (25), and a dew-point instrument (18). When the analog flue gas mixing device simulates flue gas mixture, the analog flue gas mixing device based on the high temperature humidity generator utilizes a mixed flow method to solve the problem that how to simulate a high temperature and high humidity state of the flue gas at first, and thus can simulate high temperature moisture with 0% to 30% volume occurred at the temperature of up to 165 degrees, and then adds the standard-gas with the high temperature moisture to achieve a higher gas composition and humidity accuracy based on the traceably calibrating function of the precision mirror surface dew-point instrument, so that an instrument calibration and other experiments can be achieved without being on the scene of the flue, and therefore the labor intensity of the staff is reduced and great convenience is brought for experimenters.