Nanpo Cu Mine lies at the southern part of Lanping-Simao-Mengla Mid-Axial Fracture Belt. This article has made a thorough study on the geologic features of Nan Po Copper Mine based on the on-site study and integrated analysis. In addition, a comparison study has been made for the conventional sedimentary sandstone-type copper deposit. The research indicates that Nan Po Cu Mine possesses not only the characteristics of a typical layered depositional deposit but also a late overlapping accumulation, but also the shape of the ore body, the mineral resources and the change of the surrounding rock. Moreover, Nanpo Cu Ore Deposit is characterized by sedimentation - diagenesis and ore accumulation. The author thinks that Nan Po Copper Ore Deposit is a typical sedimentary - diagenesis type in terms of geologic structure, geologic features and metallogenetic mechnism. Based on re-defining the ore-forming mode of Nanpo Copper Mine, it is believed that its lithological, palaeogeographical and structural characteristics provide a good basis for exploring the same type of Cu ore.