Abstract: The Emeishan flood basalts have high 87Sr／86Sr ratios and low εNd(t)values，suggesting that they were generated from a enriched mantle source．The diversity of Sr and Nd isotopes between early stage low—Ti(LT)and late stage high—Ti(Hr)basalts implies that they were generated from distinct mantle source and experienced different crustal contamination or assimilation．The earliest formed LTi basalts have highest 87Sr／86Sr ratios (0.7063～0.7078) and lowestεNd (t) values(-6．74～ -0．34)，while late stage HT basalts have lowest 87Sr／86Sr ratios(0.7049～0.7064)and highestεNd (t)values(-0.71～1.5)．Along with oxygen isotopes of clinopyrxene from the LT basalts ranging from 6.2 ‰ to 7.86 ‰ , higher than oceanic island basalts(5.4‰ )，this study suggests that The Emeishan flood basalts well recorded the interaction processes in both temporal an d spatial aspects．The early stage form ed low-Ti basalts mainly distributed in the western division of Emeishan large igneous province contain many crustal material signatures．The metasomatized subcontinental lithospheric mantle might be the major source for its generation．Late stage form ed high-Ti basalts occurring mainly in the middle and eastern divisions show some plume signatures and little crustal contamination or assimilation．These factors suggest that the interaction between plume head and the enriched subcontinental lithospheric mantle played an important role in the formation of the low-Ti basalts．However，it was less important for the generation of high-Ti basalts at later stage．