Numerous pull-apart basins are present along the Haiyuan fault zone in northwestern China. Detailed geological mapping of these basins reveals an evolution of faulting and subsidence that leads toward extinction of some pull-apart basins. The most common cause of pull-apart basin extinction appears to be the development of new strike-slip faults along one of the basin-margin normal faults or diagonally across the basin. The strike-slip faults may develop together with normal faults to form a complex zone within the basin. The migration of boundary strike-slip faults toward the basin center can also cause the extinction of pull-apart basins. The extinction of these pull-apart basins suggests that there is probably a tendency for a strike-slip fault zone to straighten itself, and the examples show how this takes place.