The Shuicheng-Ziyun-Nandan rift basin (SZNRB) is located in the northern margin of the YoujiangBasin.During late Paleozoic, the basin was dominated by carbonate platform-basin faices deposition including siliceous rock. Sedimentary assemblage and geochemical features of the siliceous rock are different from that of siliceous rocks in the continental shelf and accretionary complexes.Geochemical analysis for siliceous sediments indicates that siliceous deposits from the bottom of the Upper Devonian Liujiang Formation in the Nandan area and the Lower-Middle Permian Sidazhai Formation in the Hechi area were genetically associated with basaltic volcanic eruption and hydrothermal activity, and showed lower Al/(Al+Fe+Mn) and Al2O3/TiO2 values.The siliceous sediments of the Lower-Middle Permian Sidazhai Formation in the Ziyun area have a Al/(Al+Fe+Mn) value of 0.62±0.16 and Al2O3/TiO2 value of 11.70±4.30, suggesting a pyroclast-bearing nonhydrothemal origin, while the other siliceous sediments were precipitated in normal marineenvironments.During the Late Devonian-Early Carboniferous,siliceous sediments were intercalated with mudstone and limestone, and show moderately negative Ce-anomalies (0.6~0.85mostly) and higher Y/Ho values (30~45 mostly), and low ∑REE+Y values three times lower than PAAS-like composition after deducing the effect of SiO2 dilution. With rifting and expanding of the basin and, siliceous sediments was interbedded with dark thick limestoneto the Early-Middle Permian. The siliceous sediments are characterized by large negative Ce-anomalies(0.06~0.61) and a similar Y/Ho values(40~92) as that in open-ocean seawater, and a high ∑REE+Y value twice higher than PAAS-like composition after deducing the effect of SiO2 dilution.