Abstract: The Yangtze Block is one of the major cratonic blocks in China, which has been an important frontier issue on Precambrian crustal evolution for a long time. However, because continuous cap sedimentation since Nanhua period resulted in scarce outcrops of the Archean to Paleoproterozoic basement, the substance composition, tectonic attribute and evolution history of the Yangtze Block are not well constrained. Therefore, finding and identifying property and geochronology of the basement hidden below the cap are critical to tracing the Precambrian geological evolution of Yangtze Block. Based on the core of Nanhuang Complex(hidden basement) sampled from deep drilling in the Lower Yangtze region, this paper presents an integrated study of zircon U-Pb and Lu-Hf isotopes for its orthogneisses. LA-ICP-MS zircon U-Pb dating yields the protolith ages of ca. 2.71 Ga for two amphibole plagiogneisses, ca. 2.51 Ga for two K-feldspar gneisseses, providing unambiguous evidence for the presence of Neoarchean basement in the northeastern Yangtze Block. Zircons from the amphibole plagiogneisses exhibit ε_Hf(t) values ranging from −2.6 to +3.6, corresponding to T_DM2 model ages of 3.36–2.96 Ga. Similarly, zircons from the K-feldspar gneisses display ε_Hf(t) values between −4.0 and −0.7, with T_DM2 model ages of 3.29–3.08 Ga. These isotopic signatures indicate significant Early Archean (3.3–3.0 Ga) crustal growth beneath the Lower Yangtze region. When our data is combined with the existing geochronological data in other parts of the Yangtze Block, it demonstrates that the Nanhuang and Yudongzi Complexes may record the same tectonic transition from arc-continent collision (2.7 Ga) to post-orogenic (2.5 Ga) in the northern Yangtze Block, representing the Neoarchean global massive crustal reworking. Furthermore, the buried Nanhuang Complex likely participated in Yanshanian magmatism and associated mineralization events in the Lower Yangtze metallogenic province.