Thermal stability of ceramic membranes for high-temperature gas purification is the key to long-term stable operation of ceramic membrane filters. Based on the standard k?? turbulence model and porous media model, the gas flow in the ceramic membrane filter was numerically simulated. The distribution characteristics of the gas velocity field, pressure field and temperature field in the device during the steady-state filtration phase were studied. The temperature field changes in the device before and after the non-steady-pulse cleaning were compared, and the mechanism of the ceramic filter material damage caused by thermal-mechanical coupling during pulse cleaning was studied by quantitative analyses. The results showed that the model established by the simulation can more realistically reflect the field distribution characteristics of the gas in the whole process of hot gas filtration and pulse cleaning. During the steady-state filtration stage of the hot gas, the gas velocity was higher at the inlet and outlet pipes compared to those in the dust-containing chamber and the clean air chamber. The gas velocity in the filter tube gradually increased along the axis of the tube, while the gas pressure gradually decreased. The filter temperature did not change with the change of position. During the non-steady-state pulse cleaning stage, the temperature field of the gas near the blowback inlet formed a low-temperature region, which was distributed in an almost elliptical shape in the axial section of the tube. It should be emphasized that the temperature at the inner wall of the tube first decreased and then rose along the axial direction. However, the temperature of the gas in the tube gradually increased and the temperature in dust-containing chamber was almost unchanged. At a distance of 0.0664 m from the top of the ceramic tube, the material was subjected to the greatest thermal stress of 2.8 MPa, which was the most vulnerable position during the pulse cleaning process.