The coda-wave attenuation factor Qc in the Xiaojiang fault zone is estimated through the Aki’s single-scattering attenuation model based on the seismic events from January 2000 to December 2009. The relation between Qc and f at the 10 stations is fited as Qc(f)=Q0f0.81. The Qc-value in the Zone is lower than the ones in the other areas of Yunnan Province. The Qc-value in the middle part of the Zone is much lower than the ones in the north and the south part of the Zone. The relationship between the temporal variation of Qc-value and the mid-strong earthquakes is also studied.