Abstract In this paper, we collect digital waveform data both from mobile stations and permanent stations, and study the shear-wave splitting characteristic of Wulong M5.0 earthquake sequence based on SAM method. We obtain 94 pairs of shear-wave splitting parameters from 5 stations. The results show that the fast polarization directions (FPDs) are generally NW direction, which is obviously controlled by regional principal compressive stress field. The variation of the dominant FPDs from NW to NNW is affected by several NE-trending faults and complex structures in the region; the dominant FPDs of stations in the east and west of the mainshock show a certain spatial distribution change. The FPDs are scattered in the early stage after the mainshock and become stable in the late stage, indicating the regional stress tends to stabilize in the late stage. The delay time basically increased before strong aftershocks. However, the delay time decreased in a short time before some strong aftershocks. It is coincides with the long-term stress accumulation and short-term stress relaxation before earthquakes. There is no obvious relation between the delay time and the focal depth.