Major element, trace element and Sr_Nd isotope data of two types of Late Mesozoic metaluminous and high_K calc-alkaline intermediate_felsic volcanic rocks from the Lishui Basin in Lower Yangtze valley are reported in thispaper. The first type is represented by the trachyandesites occurring in the Longwangshan Formation. These rocks span a SiO2 range of 58.0%～58.9%, characterized by significant LILE (e.g.,Rb=104×10-6~117×10-6, Ba=651×10-6～695×10-6)and LREE (e.g.,Ce=47.44×10-6～4896×10-6)and Nd-Ta depletion with insignificant Eu anomalies (Eu/Eu*=0.87～1.01,with an average of 0.95), and similar Sr and Nd isotopic compositions[87Sr/86Sr(i)=0.705?51～0.705?57, εNd(t)=-3.6～-2.9］to thecontemporaneous mafic lavas. These rocks are spatially coeval with the mafic volcanic rocks and are interpreted as the differentiates of the basaltic magmas after removal of a fractional assemblage of amphibole + plagioclase + apatite. The second type is composed of trachytes occurring in the Dawangshan Formation. These rocks span a SiO2 range of 61.9%～66.4% and MgO range of 1.07%～2.56%,showing similar trace element features to trachy-andesites of the Longwangshan Formation. Compared with basalts and trachyandesites from the Longwangshan Formation, they have higher k2O, Rb, Th, REE, HFSE, lower FeOT, TiO2, P2O5, CaO, Sr and compatible element contents, and more radiogenic Sr and less radiogenic Nd isotopic compositions [87Sr/86Sr(i)=0.706 63～0.708 13; ε Nd(t)=-7.7～-4.8］. The unique characteristics (e.g., K-rich, metaluminous and dacitic compositions) in these rocks argue against an origin of crust_derived melts. It is thus considered that these melts as differentiates of the primary basaltic magmas were subjected to as similation and fractional crystallization. 