The southwest margin of the Yangtze Block played an important role in the amalgamation and fragmentation processes of the Columbia supercontinent, but the tectomagmatic evolution of the late Paleoproterozoic is insufficient and controversial. In this study, Paleoproterozoic regenerated granite was found in Lufeng area of central Yunnan Province, southwest margin of Yangtze Block. It was formed by the rapid sedimentation of weathered K-feldspar granites within the Paleoproterozoic Lüzhijiang Formation. The main components are quartz, potassium feldspar, a small amount of biotite and plagioclase. LA-ICP MS zircon U-Pb dating, Lu-Hf isotope, rock geochemistry and zircon trace element analysis showed that: the weighted average 206Pb/207Pb age of zircons is 1849±6Ma (MSWD=0.11, n=21). The εHf(t) values of 7 zircons range from -7.23 ± 0.7 to -3.58 ± 0.75, with an average of -5.2 ± 1.2, and the TDM2 is 2819±73Ma. The trace element characteristics of zircons and petrogeochemical features indicate that the protolith was S-type granite, possibly derived from the melting of metasedimentary rocks in the Middle Archean. The discovery of Paleoproterozoic regenerated granites indicates the existence of S-type granites of ~1.85Ga in the southwest margin of the Yangtze block, providing a new evidence for the tectonic chronology and petrology of the Columbia supercontinent. It also shows that the formation of Lüzhijiang Formation in central Yunnan Province is Paleoproterozoic, providing new data for the Precambrian geological research in central Yunnan Province.