Abstract: Taking Chifeng and its surrounding areas as the research area, the waveform records of 128 earthquakes with M_L ≥ 2.5 recorded by 17 stations since 2013 are selected, and the temporal and spatial variation characteristics of coda Q_C value are calculated and analyzed based on Sato model. The results show that the relationship between Q_C value and frequency is Q_C (f) = (58.34±25.88) f ^{(0.9118±0.0849)}. The attenuation parameter Q₀ is inversely proportional to the frequency dependent parameter η; Q₀ is high in the west and low in the east, and is closely related to fault structure, seismicity and bedrock lithology; The results of retrospective test show that before and after the Tongliao M_S5.3 earthquake, the Coda Q value in the focal area manifests a typical change process of "decrease before earthquake, rise before earthquake and recovery after earthquake". It shows that the heterogeneity, attenuation characteristics, medium stress state and seismogenic information of the crustal medium body in the focal area can be analyzed by the temporal and spatial variation of Coda Q value.