Located in the southeastern part of the south China continent，Fujian Province is characterized by a complex crustal architecture. This architecture is considered to be the result of Paleo-Pacific plate subduction and multiple tectono-magmatic events. The spatial distribution characteristics and dynamic mechanisms of crustal anisotropy，thickness，and Poisson’s ratio in the region were revealed using harmonic analysis of the far-field P-wave receiving function and an improved H-κ-c stacking method. The results show a NW-SE oriented fast polarization direction for the crustal anisotropy. The mean splitting time is found to be 0.26 s. This direction is consistent with the regional extensional stress field. Plate rollback and back-arc extension are identified as the dominant controlling factors. Near major faults，the fast axis is observed to parallel the fault strike，reflecting the influence of fault activity. The coastal crust is measured to be 28~31 km thick. Inland crustal thickness is determined to be 30~35 km. Sharp steps in crustal thickness are noted across the Changle—Zhaoan and Zhenghe—Dabu faults. These faults are shown to be trans-crustal structures that control the crust-mantle geometry. The high wave velocity ratio along the coastal areas （>1.78） is related to mantle upwelling and crustal melting，while the low value inland （<1.73） is attributed to quartz-rich granites in a stable tectonic setting. In addition，there is a significant negative correlation between crustal thickness and wave velocity ratio in the region，suggesting that the subduction of the ancient Pacific plate caused mantle material upwelling，resulting in crustal thinning and an increase in Poisson’s ratio. The research results provide new geophysical constraints on the crustal composition and tectonic evolution of Fujian. The importance of plate subduction，back-arc extension，fault activity，and crust-mantle interaction is highlighted.