Based on geological investigation, this paper studies the whole-rock element geochemistry, zircon U-Pb geochronology and Sr-Nd-Pb isotopic compositions of the Guandimiao granitic batholith in Hengyang City, Hunan Province. With reference to previous research, we discuss petrochemical property, forming age, material sources as well as diagenetic mechanism of the Guandimiao granitic batholith. The study shows that the Guandimiao granitic batholith is characterized by high silicon, high potassium, metaluminous as well as rich in Ligh Rare Earth Elements (LREEs) and Large Ion Lithophile elements (LILEs, Rb, Th, U, K), while depleted in Heavy Rare Earth Elements (HREEs) and High Field-Strength elements(HFSE, Nb , Ta, Ti) , Ba and Sr. Zircon LA-ICP-MS U-Pb dating yields a weighted mean age of 223.4 ± 1.9 Ma (MSWD = 0.48, 2σ, N = 13). Sr-Nd-Pb isotopic study shows relative high initial 87Sr/86Sr radios (0.712005 ~ 0.713631), low εNd(t) values (-9.95 to -9.59) and old two-stage model ages of Nd isotope (TDM2 = 1.78 ~ 1.81 Ga), and characterized by uniform initial Pb isotopic ratios [(206Pb/204Pb)i, 18.161 to 18.316; (207Pb/204Pb)i, 15.686 to 15.743; (208Pb/204Pb)i, 38.622 to 38.772]. During the late Indosinian, South China was in the environment of post-collisinonal tectonic setting of orogenic stage. With the stress receding or extrusion eased, the mantle-derived mafic magma underplated and induced the Paleoproterozoic lower crust partial melting, forming granitic magma. The granitic magma transported along the faults, then emplaced and formed the Guandimiao granitic batholith.