In this study, we collected the P-wave first motion data of small earthquakes that have occurred in the middle-southern segment of the Tan-Lu fault zone since 2009. We used the grid point test method to obtain the integrated mechanism solutions of small earthquakes recorded by 51 stations and the focal mechanical solutions of 167 moderate and small earthquakes. The results show that the direction of the principal compressive stress is close to NEE and nearly EW in the study area and that there are local differences in the crustal deformation in the middle-southern segment of the Tan-Lu fault zone. The segmental characteristics of the regional deformation, as reflected by composite mechanism solutions for different station types, have a close correlation with the tectonic background and stress field in the study area..