The greisen inclusions usually irregularly occur near the top of the grey alkali feldspar granite in the tungsten deposits of the Nanling tungsten belt. Studies of geology and geochemistry of the inclusions from the Yaogangxian tungsten deposit in Hunan Province show that the greisen inclusions were formed from liquid immiscibility of the Li-F alkali feldspar granite magma, which produced magmatic-hydrothermal transition state and hydrothermal solution. The formation of the vein-type tungsten deposit was related to stage Ⅰ gray alkali feldspar granite. The greisen inclusions constitute an important indicator for evaluating the granite in search for ore deposits.