On June 30, 2012, an M_S6.6 earthquake occurred at the border of Xinyuan and Hejing in Xinjiang. This study inversed the spatial distribution of the consistency parameter Var (variance) and the azimuth of the mean maximum principal compressive stress P axis and found some changes in these parameters. First, on the basis of the waveform data of January 2009-May 2013 recorded by the Xinjiang Seismic Network Center, we used the cut-and-paste and P-wave first motion methods to inverse the focal mechanism solutions of 418 small-to-moderate earthquakes around the main shock area of the above mentioned M_S6.6 earthquake. Then, we inversed the consistency parameter and azimuth variation of the mean principal compressive stress P axis. From the study results, we derive three conclusions. First, prior to the main shock, around the seismogenic zone, the Var value was relatively low, which means that the earthquake action was affected by the stress field of the seismogenic zone. After the main shock, the Var value significantly increased, which means that the control of the background stress field began to strengthen. Second, prior to the main shock, the stress near the epicenter area began to concentrate, and the azimuth of the mean maximum principal compressive stress P axis was consistent with the main shock. However, after the main shock, this azimuth exhibited a certain angle from the main shock and was consistent with the azimuth of the regional stress field. Third, prior to the main shock, the Var value was relatively low, and the azimuth of the maximum principal compressive stress P axis was not consistent with the historical average value.