In order to elucidate the tectonic mechanism during the transition from collisional to intra-continental orogeny, the zircon U-Pb dating and whole-rock major and trace element geochemistry of intermediate-acidic dykes in the Xiahe-Hezuo Area of the West Qinling Orogen, China, were investigated. Whole-rock geochemical data reveals that the intermediate-acidic dykes in the Xiahe-Hezuo area show high Si (59.95% ~ 67.41%), rich K (2.08% ~3.40%), low Na (1.42% ~ 2.80%), and near-aluminous to weakly peraluminous (A/CNK = 0.77 ~ 1.17) geochemical characteristics, and classified as high-K calc-alkaline I-type granites. Total rare earth element (REE) contents vary from 128.06 × 10^-6 to 209.47 × 10^-6, with significant enrichment of light REE (LREE=104.96 × 10^-6 ~ 182.63 × 10^-6) and marked depletion of heavy REE (HREE = 19.91 × 10^-6 ~ 28.01 × 10^-6), resulting in a high LREE/HREE ratio (3.92 ~ 7.73). Additionally, the dykes show enrichment of large ion lithophile elements (Rb, K, Th, Li) and depletion of high field strength elements (Nb, Ta, P, Ti). Zircon U-Pb dating indicates that the dykes formed during the Late Early to Late Middle Triassic [(232.4 ± 1.4) Ma to (248.0 ± 1.1) Ma]. Based on the regional geological setting, the intermediate-acidic dykes was indicated to form under a tectonic setting characterized by crustal shortening and thickening due to plate collision, involving underplating of mantle-derived magmas and partial melting of high-K basic lower crust, with possible contribution from mantle-derived magmas. The transition from collisional to intracontinental orogenesis in the West Qinling Orogen is proposed to have occurred between 231 Ma and 248 Ma, based on integrated geochronological data from Triassic intermediate-felsic plutons.