Volcano-intrusive rocks in the Mesozoic volcanic belt along the northern margin of Dabie Mountains can be subdivided into three rock series, i.e., high-potassium calc-alkaline series (HKCA), alkaline series (A) and shoshonitic (SHO) series. 14 samples were measured for the Rb-Sr and Sm-Nd isotopic compositions, and the results show that the initial Sr ratios (ISr) are 0.707 50~0.710 54, 0.708 43~0.710 14 and 0.708 73~0.709 12, the initial Nd ratios (εNd) are -17.2~-19.1, -14.7~-15.8 and -20.7~-21.7, and the two-stage depleted-mantle model ages (TDM) are 2.32~2.48Ga, 2.12~2.20 Ga and 2.60~2.68 for HKCA, A and SHO, respectively. A comparison of Nd isotopic composition between these vol cano-in-trusive rocks and the basement metamorphic rocks shows that the HKCA rocks were mainly derived from the Dabie Group-like crustal rocks, alkaline rocks were mainly derived from Dabie Group with small amounts of younger crustal rocks (Luzhenguan Group and Foziling Group), and the shoshonitic rocks were mainly derived from enriched mantles probably with incorporation of small amounts of even older Taishan Group_like crustal rocks.