Abstract: Several bauxite deposits have been discovered in north area of Wushi,Xinjiang,recently. These bauxite deposits are situated in the edge of passive continent margin of Carboniferous system in south Tianshan where the Ayili River is the bauxite-enriched center,with the o re body stead ily ex tend ing in N E and SWd irections in this region. On the basis of Ayili River ore deposits,we expound the ore-forming geological conditions,bauxite-bearing stratum,and deposit character in this area. The commercial bauxite deposits a reformed in three eroded surfaces of middle carboniferous limestone,dominated by bedded and lenticular ore bodies,whose pattern and size are controlled by the eroded surfaces and ancient landform.