The ~2.5 Ga granitic rocks reported in this article are newly discovered from the Xiaochang and Susong areas in the Dabie Mountains (Dabieshan), which provide a very rare but direct record of the continental crust at the turn of Archean—Proterozoic in the Yangtze Block basement. Petrological and zircon chronological studies of these granitic rocks were conducted to constrain the nature of ~2.5 Ga crust in the Dabie orogen, which gains our new insights into the composition, architecture, and cratonization processes of the Neoarchean Yangtze Block.Methods:Based on the field investigation and microscope observation of the granitic samples, we conducted zircon CL imaging and LA- ICP- MS zircon U- Pb dating.Results:Zircons from the two mylonitic biotite- granite samples in the Xiaochang area are generally euhedral and long prismatic with clear oscillatory zoning, which is typical of magmatic zircon. Analyzed zircons from the two samples have Th/U ratios ranging from 0.21 to 0.55. The two samples yielded weighted mean zircon n(207Pb) /n(206Pb) ages of 2479±17 Ma (n=9, MSWD=0.45) and 2497±20 Ma (n=6, MSWD=1.11), respectively, representing their formation ages. Zircons from the two potassic granitic gneiss samples in the Susong Complex area are subhedral to euhedral with subrounded to long prismatic shapes. Most of the grains show oscillatory zoning but some blurred, chaotic internal structures under CL images. Th/U ratios of the dated zircons from both samples show a relatively large range between 0.09 and 0.81, indicating an igneous origin. The two samples were dated at 2491±15 Ma (n=9, MSWD=0.42) and 2516 ± 26 Ma (n=4, MSWD=0.50), respectively.Conclusions:Newly identified ~2.5 Ga granitic rocks from the Xiaochang and Susong areas suggest that crust of these ages should have been widespread in the Dabie Mountains. This indicates that some basement rocks of the Yangtze Block were extended beneath, and currently preserved in, the Qinling—Dabie orogenic belt, and Archean crust of the Yangtze Block was more widespread than previously recognized. The turn of Archean—Proterozoic could have been a critical period in the crustal generation and cratonization of the Yangze Block basement.