Preparatory field investigation reveals that the surface deformation zone of the Qinghai-Xinjiang MS 8.1 earthquake on November 14, 2001 distributes along the south foot of Kunlunshan mountains, and may terminate at the Bugedabanfeng as the western end while the eastern end is tracked down at the point 70 km east from the Qinghai-Xizang Raod.The total length of the deformation zone reaches 350 km.The deformation shows clear strike-slip feature and the maximum horizontal offset is found to be 6 m.It was temporarily determined that the macro-epicenter is 30 km east from the Kusaihu lake, and the intensity in the macro-epicenter is Ⅺ.It's suggested that the earthquake be named as Kusai hu earthquake.