Studies on volcanic ash in bauxite-bearing rock series of Permian in western Guangxi were focused on its connection with mineralization, but there are hardly case about defining tectonic evolution and magmatic activity. In recent years, magma recharge has become a hot spot in the study of magmatic evolution, and abudant volcanic ashs in bauxite-bearing rock series in Chongzuo area is just an excellent window for observing magmatic activities.This paper attempts to further clarify the properties and eruption mechanism of volcanic ash in the Permian bauxite-bearing rock series. Methods: Line investigation, zircon geochronology, microscopic research and element analysis.Results:The volcanic ash of Permian bauxite-bearing rock series from Chongzuo area consists of detritus, crystal fragment, hyaloclastic fragment, volcanic dust. The detritus is mainly basaltic andesite, followed by basalt and a small amount of acidic rock, and composing a calc- alkaline series. The contents of Fe, Ti, Cr and V are high, among which the average value of Cr is 769.37×10-6, meanwhile the contents of rare earth are 121.9×10-6~433.0×10-6, with an average of 284.98×10-6, whereas δEu varies from 0.46~0.94, with an average of 0.78; It is rich in Th, U, Pb and LREE, but depletion in Nb, Ta, Sr and HREE. Fragment of cumulative crystal indicates the presence of magma reservoirs and the breakdown of the crystal mush. The andesitic volcanic ashes are mainly composed of antecrysts, few peritectic crystals and xenoliths, which reflect that magma recharge had been practised, and the content of inactive elements fluctuates greatly, and the variation range of Nb/Ta and Zr/Hf includes the chondrite — continental crust category, and the variation of δEu is large, indicating mixing of high differentiation and low differentiation magma.Conclusions: The volcanic ash has derived from the oceanic arc, and magma for recharge were mafic.