The late Carboniferous vulcanco-sedimentary sequences of Bieluwutu Formation consist mainly of tuffaceuus sediments, albite-rich rhyolite porphyry, rhyolitic tufflava，rhyodacite and andesite with minor amounts of basalt.The tectonic setting of the Bieluwutu Formatiun is a Late Paleozoic rift basin a1ong the paleocontinental margin. Sm-Nd isotopc data on albite-rich rhyolite porphyry , rhyolitic tufflava，andesite and basalt are presented in this paper. Nine whole rock samples of andesite acid basalt give an age of 275±5.2 Ma（2δ），INd＝0.512143±30（2δ）and εNd(ｔ)＝-2.7±2.2（2δ），which may represent the time of mafic volcanic eruption of the Bieluwutu Formatiun. The basalt and andesite were derived from a REE-rich mantle source, and contaminated by the continental crust. The εNd(275Ma) value of the albite-rich rhyolite porphyry and rhyolite tufflava ranges from -6.3－-5.4，which is much lower than that of andesite and basalt. Combined with other field and geologic evidences，the authors believe that these felsic volcanic rocks must have been originated from remelting of the continental crust during the mafic volcanic eruption of the Bieluwutu vulcano-sedimentary Formation.