Abstract: The sedimentary study of Sunan mining area deals with the paleotopography before Cenozoic bottom sedimentation,the size of grains and frictional extent of grains,the origin of sediments,the profile of sediments and the sedimentary facies.Based on that the sedimentary model for this area is established.What above done has much meaning for studying hydro-geological characteristics of the area and for controlling water from Cenozoic bottom's aquifers.