Using digital seismograms recorded by the Gansu digital seismic network, the inelastic attenuation coefficient is calculated based on a genetic algorithm and the method proposed by Atkinson. Then, the site response and source parameters are investigated by the Moya method. The inversion results indicate the frequency-dependent inelastic attenuation, Q value, in the southeastern Gansu is estimated as Q(f)=404.2f~ 0.264 . Except for the Tianshui station, the site responses of the other stations do not show significant amplifications,which is consistent with their basement on rocks. The stress drops of all 39 earthquakes range between 1×10~5 and 7×10~6 Pa. We also found the dependence of corner frequency on seismic moment and seismic magnitude. Using digital seismograms recorded by the Gansu digital seismic network, the inelastic attenuation coefficient is calculated based on a genetic algorithm and the method proposed by Atkinson. Then, the site response and source parameters are investigated by the Moya method. The inversion results indicate the frequency Q, in the southeastern Gansu is estimated as Q (f) = 404.2f ~ 0.264. Except for the Tianshui station, the site responses of the other stations do not show significant amplifications, which is consistent with their basement on rocks. The stress drops of all 39 earthquakes range between 1 × 10 ~ 5 and 7 × 10 ~ 6 Pa. We also found the dependence of corner frequency on seismic moment and seismic magnitude.