Considering the influence of the thin-film residual stress and surface impurities of deformable mirrors (DMs), the stress analysis model of the DM with high reflectivity films was built up by the use of the finite element analysis software ANSYS. The fatigue damage characteristics of the DM for wavefront correction process were analyzed based on the stress-cycle (S-N) curve and the Miner cumulative damage theory, and the influence of the thin-film residual stress and the surface impurity size on the fatigue life of the DM was discussed in detail as well. The results indicate that, under the condition of the thermal-mechanical coupling, the fatigue damage of the DM tends to speed up due to the thermal effect. For a given distortion wavefront to be corrected, the dynamic cyclic load of the DM is stronger with the increasing thin-film residual stress of the DM, and the fatigue life is shorter simultaneously. Besides, the residual stress mainly affects the fatigue life on the surface of the DM. For the given thin-film residual stress of the DM, the fatigue life also decreases due to larger surface stress caused by the increasing PV value of the distortion wavefront. When the surface impurities are irradiated by the high-power continuous laser, and are above a certain size, the fatigue life of the DM decreases with the increasing impurity size. However, the fatigue life of the DM is rarely affected when the sizes of the impurities are smaller enough. Furthermore, the thin-film residual stress will further increase the fatigue damage of the DM caused by surface impurities.