The granitic pegmatites in the North Qinling tectonic belt represent one of China' s most significant pegmatite areas. However, their formation age and petrogenesis remain subjects of debate.This paper presents LA- ICP- MS zircon U- Pb ages, Hf isotopic data, and geochemical analyses of the Xiahecun and Shanghecun granitic pegmatites in the Guanpo area toconstrain their formation ages, magma sources, petrogenesis, and tectonic setting. LA- ICP- MS zircon U- Pb dating reveals that the Xiahecun and Shanghecun granitic pegmatites crystallized at 361~360 Ma and 334. 8 Ma, respectively. Both pegmatites contain garnet, muscovite, and tourmaline, with high SiO2, Na2O, and K2O contents but low CaO, TFeO, and MgO concentrations, exhibiting a mainly peraluminous composition. They display little fractionation between LREE and HREE and exhibit obvious positive Eu anomalies. The magmas are enriched in large ion lithophile elements (LILEs; e. g. , Rb, Th, Ba, and Cs) but depleted in high field strength elements (HFSE; i. e. , Nb, Ta, and Ti), with low Nb/Ta and Zr/Hf ratios, indicating a high degree of crystallization differentiation. The Xiahecun granitic pegmatite has low εHf values (11. 7 to 6. 2), whereas the Shanghecun granitic pegmatite shows higher εHf values (4. 9 to 1. 1). These findings imply that the Xiahecun granitic pegmatite originated from partial melting of ancient crust, while the Shanghecun granitic pegmatite formed through partial melting of juvenile lower crust, followed by magma assimilation and wall- rock contamination. In the eastern part of the North Qinling tectonic belt, the granitic pegmatites can be divided into two types: northern rare- metal granitic pegmatites and southern uranium- bearing granitic pegmatites.