As the technology of flue gas flooding is increasingly used，the severe corrosion of the flue gas on the wellbore arises becomes more important. Corrosion experiment on N80 steel was conducted at simulated high temperature and high pressure using the flue gas corrosion testing device. The composition and morphology of the corrosion product were analyzed by X-ray diffractometer，scanning electron microscope and energy spectrometer. The effect of temperature，pressure，flow velocity and O2 and SO2 content on the corrosion rate of N80 steel was studied. The results show that the corrosion rate decreases fast with the increase of time and gradually reaches to a stable state after 72 h under the simulated dynamic corrosion environment of flue gas at high temperature and pressure. The corrosion product of N80 steel is mainly composed of FeCO3，Fe3O4 and Fe2O3. The corrosion product was arranged disorderly with incomplete coverage and annular distribution.The corrosion rate increases with temperature when the temperature is lower than 60 ℃ and reaches to the maximum at 60 ℃. When the pressure and the concentration of carbonic acid increase，the corrosion rate increases. With the increase of flow rate and oxygen content，the corrosion rate increases. With the increase of SO2 content，the corrosion rate shows a trend of decreasing first and then rising.