Shear-wave splitting analyses were performed at 30 seismic stations in the central Tien Shan and its vicinity. Fast orientation at most of the stations on the Tien Shan range is ENE-WSW, parallel to the strike of the Tien Shan. It largely reflects a coherent deformation of the lithosphere in response to the NS shortening. Anisotropy with NNE-SSW fast axes is observed within adjacent basins, around the Issyk Kul and near the northwestern Tarim, where the lithosphere is presumably strong, less deformed. The NNE-SSW orientation, which coincides with the surface velocity of the central Tien Shan, can be best explained by shear between the lithosphere and asthenosphere on a regional scale rather than small-scale convection as proposed in previous studies. The dextral Talasso-Fergana fault seems to have little effect on anisotropy at its nearby stations, suggesting this fault is probably confined to the shallow part of the lithosphere.