Abstract: A series of dikes composed of gabbros and granodiorite porphyries are developed near the Xucun town in the Southern Anhui Province .The dikes are inseparably associated in time-space and closely related in genesis .The SiO2 contents in the rocks from the dikes are concentratedly a lack of SiO 2 contents between 56% ~63% consistent with the intermediate and intermediate-acidic composition ranges ,constitu-ting an assemblage of bimodal intrusive rocks .The high-precision LA-ICP-MS U-Pb zircon dating of 822 ± 6 .6Ma obtained by the present study may indicate The intrusion age of the bimodal dikes .The gabbros have positiveεHf (t) values of 2 .1~4 .4 ,enriched large ion lithophile elements and LREE ,showing charac-teristies of petrochemical and isotopic compositions of the continental tholeiite basalts .The granodiorite porphyries have enriched Zr ,Hf and REE ,relativity higher Ga/Al values ,and relatively lower Ba ,Sr ,P ,Ti , being overall analogous to the geochemical characteristics of A 2-type granites ,withεHf (t) values of 1 .8~4 .6 basically similar to those of gabbros .Therefore ,in the Xucun series of bimodal dikes ,the basic and member gabbros may have produced from the basaltic magma originated by the partial melting of the de-plated lithospheric mantle in South China in a tensional settling ,whereas the acidic end member granodior-ite porphyries are likely resulted from the remelting of the crust caused by the heat source provided by the basaltic magma during its upwelling and underplating accompanied by hybridism of the crust .