Abstract: The Miwu pluton, located in the western segment of the West Qinling orogenic belt, constitutes a key magmatic record of the subduction and closure of the A'nyemaqen-Mianlue oceanic basin during the orogenic process.To constrain its petrogenesis, this paper presents an integrated study of petrography, geochronology, and geochemistry on the biotite granodiorite and its associated mafic enclaves. Zircon U-Pb dating yields ages of 240.1±1.3 Ma for the host granodiorite and 247.0 ±2.1 Ma for the enclaves, indicating an Early-Middle Triassic origin, with the enclaves being distinctly older than the host rock. The mafic enclaves are fine-grained diorite in composition and are characterized by K₂O contents of 1.16%-3.25%, K₂O/Na₂O ratios of 0.33-1.07, A/CNK values of 0.68-1.00, and Rittmann indices(σ)of 1.49-2.95, classified as metaluminous, calc-alkaline to high-K calc-alkaline series rocks. The host biotite granodiorite exhibits K₂O contents of 3.87%-4.11%, K₂O/Na₂O ratios of 1.26-1.40, A/CNK values of 0.96-0.99, and Ritmann indices (σ)of 1.97-2.04, belonging to the metaluminous to weakly peraluminous, high-K calc-alkaline series and being classified as I-type granites. Both the host rock and enclaves are enriched in LILEs(Rb)and incompatible elements(U, Th), and relatively depleted in HFSEs(Nb, Ta, Ti, P). They both show relative enrichment in LREEs, with the host granodiorite displaying a weak negative Eu anomaly. The mafic enclaves are interpreted as wall-rock fragments captured during the emplacement of the host granodioritic magma. It is proposed that these enclaves likely represent mixed magmatic rocks formed through MASH(melting, assimilation, storage and homogenization)processes involving hydrous mafic magmas derived from a subduction-related mantle wedge and lower crustal materials.Subsequently, they were disrupted and transported to shallow crustal levels by the later emplaced granodioritic magma.The Miwu Pluton is inferred to have formed in an active continental margin setting associated with subduction.