Jingde pluton is a typical high Sr/Y granodiorite emplaced in the eastern Jiangnan Orogen, China. New LA-ICPM zircon U-Pb dating for one diorite yields an emplacement age of 141±1Ma. The pluton is composed of monozograntie and granodiorite. The biotite in the pluton falls into Mg-type. plagioclase is mainly oligoclase and andesine. The pluton possesses high SiO2 ( 66.01% ~ 70.87%), Al2O3（14.91% ~16.24%），total alkalinity（K2O+Na2O＝6.64% ~ 8.01% ），K2O/Na2O（0.78~1.04），Sr（189 ×10-6 ~ 452×10-6）and LREE，low HREE and HFSE contents， and slightly negligible to positive Eu anomalies (δEu＝0.81~1.18). Consequencely, the samples have high Sr/Y（23 ~ 66）and (La/Yb)N（13 ~ 58）ratios. On the other hand, they have low MgO (or Mg#), Cr and Ni contents. The pluton has relatively higher Nd isotopes (εNd(t)＝‒12.92~‒6.28) and younger tDM2 model ages（1.4~1.9Ga）, with mafic microgranular enclaves (MMEs) suggesting the importance of mantle material in the magma source. The mafic magmas ascended from the metasomatized and heated the lower crust, triggering partial melting to form the Jingde pluton, with input of mantle-derived materials.