Abstract:The Xiangyangping uranium deposit is the most representative granite-type uranium deposit in the Miao'ershan area of northern Guangxi. Based on the detailed field investigation, the main uranium mineral in the deposit is pitchbiende. LA-ICP-MS REE research dissects the source of ore-forming fluids. The results show that oxidized pitchblende ∑REE is 689.12×10-6~869.31×10-6, LREE is relatively enriched, HREE is relatively deficient, strong Eu is negative and Ce is positive, TE1,3 values range from 1.26 to 1.33, with a typical M type REE tetrad effect; the ∑REE of the pitchblende is 569.73×10-6~3 337.83×10-6, showing two characteristics:① LREE enrichment, HREE loss and LREE and HREE fractionation degree are large, Eu exhibits strong negative anomaly but weak Ce positive anomaly, and chondrite-normalized REE patterns are right-included; ② LREE and HREE fractionation degrees are small, Eu negative anomaly is obvious, Ce negative anomaly is weak, and the chondrite-normalized patterns of REE are in seagull type form. The fresh rock has similar chondrite-normalized REE patterns, and the Y/Ho ratio range is narrow, indicating that it has the same material source. REE of ore minerals are quite different from the values of the fresh rocks, and the kindship is not obvious. The alteration and high uranium background is a product of the mineralization. The ore-forming fluid is multi-stage rich in U-Y-REE. The uranium mainly cane from deep hydrothermal fluid, and the contribution of fresh rock is not significant. The location of the deposit is controlled by the combination of tectonic and rock mass. The size and shape of the orebody are determined by the tectonic scale and modes of occurrence.