Abstract: In Kusilafu area, southwestern Tarim Basin, the sandstone-type copper deposit was developed in the rift basin of late Paleozoic's early period continental margin.Ore-bearing rocks are coastal-shallow coastal clastic + carbonate constructions.Ore body occurs in the light-colored clastic rocks of Devonian light-purple interlayer, which was constrained by certain layer, with the geological characteristics of sedimentary deposit.The trace and rare earth elements of ore-bearing rocks show that, the Precambrian crystalline basement in the west side of this deposit may provide some material source for the initial concentration of this copper deposit.The ore body was occurred wall rock alterations (such as carbonization and siliconization) along the tectonic zone (line).And the source layer of this deposit might be transformed and enriched by the Early Carboniferous intermediate-basic volcanic magmatic activities, thus this deposit performs the characteristics of sedimentation-hydrothermal reworked deposit.And the copper mineralization was developed in the similar layer, showing a potential of forming middle-large sandstone-type copper deposit in this region.