To investigate the composition and evolution characteristics of early crystallization basement in the Dabie orogen, we analyzed the petrology, geochemistry, zircon U-Pb chronology and Lu-Hf isotopic composition of biotite-hypersthene-plagioclase gneiss exposed in the Huilanshan area of this orogen. The result shows that its protolith is quartz diorite with a formation age of Paleoproterozoic (2463±22 Ma), and experienced Paleoproterozoic granulite facies metamorphism with an age of 2002±11 Ma (MSWD=0.46). Zircon Ti geothermometer shows that the metamorphic temperature is about 767~827℃ (average 799℃). The quartz diorite gneiss shows low SiO₂ contents (55.16%~57.10%), high MgO (4.74%~5.89%) and high Mg# values of 47.5~50.4 indicating that it belongs to calc-alkaline series, is enriched in LREE and relatively depleted in HREE ((La/Yb)N=19.3~34.1), with no obvious Eu anomaly ((Eu/Eu*)= 0.9~1.2). It also has high Sr, Ni, Cr content, and lower YbN value and Y content, and is enriched in LILEs (Rb, Ba, K), depleted in HFSEs (Nb, Ta, Zr, and Hf), which is similar to the magnesian diorite. Zircon cores from the gneiss sample have a similar Lu-Hf isotopes value of ε Hf( t ) (+2.69~+3.79) and second-stage model ages ( t DM2=2797~2739 Ma). We propose that the quartz diorite gneiss may be the product of interaction between the magma produced by dehydration melting of subduction slab and mantle magma. The granulite facies metamorphism at 2.0 Ga may be related to Columbia supercontinent assembly event. In combination with previous research in the North Huangling and the Dabie area, there may have been a “micro-continent group” with similar geotectonic position since the Paleoproterozoic, and they gradually assembled into a unified basement of the North Yangtze block during the global Columbia supercontinent convergence event.