There are a lot of layers of Palaeogene ang Neogene halite which are widely distributed in Kuqa basin. So Kuqa basin is one of the inland salt basins in which it is the most hopeful to search potash in China. It stably subsided after its formation. During Palaeogene ang Neogene salt-forming, Kuqa basin experienced strong-weak-strong tectonic stages, and its center of subsidence moved gradually from north to south and depocenter from northwest to east and southeast. Because of tectonic differentiation, series of second depression formed in Kuqa basin. The multiphase tectonic activities above clearly controlled the move and gather of salifying brine, the strongth of salt-forming and the deposition of salt-bearing strata. With the pass of time, the salt-bearing strata thickened gradually from northwest to east and southeast, and the distribution of the thickness trended towards complicated; the measurement of the halite deposition extended towards east too; in the early Palaeogene and the Neogene, strong multiphase tectonic activity was a disadvantage to salt-forming, but in the middle and late Palaeogene, weak multiphase tectonic activity, which resulted in slow and sustained subsidence of the basin, was greatly advantaged to it, especially to potash-forming. The result of the basin's tectonic differentiation and the development of the salt-bearing strata indicate that in Palaeogene ang Neogene, the Kuqa basin had already had the tectonic environment in which the potash evaporite formed.