Abstract: The Fe-Al rock series is widely developed on the top of the Emeishan basalt in northwestern Guizhou Province. In order to ascertain the characteristics of the Fe-Al rock series and explore the enrichment characteristics of its three rare elements, the authors carried out a field survey on it. The results show that the Fe-Al rock series as the weathering crust at the top of the Emeishan basalt is apparently different when the overlying stratum is Xuanwei Formation (P₃x) or Longtan Formation(P₃l). Sample test results show that the Fe-Al rock series is rich in three rare elements such as Sc, Nb, REE, with great prospecting prospects. The Sc, Nb and REE contents of the Fe-Al rock series with Xuanwei Formation (P₃x) is higher than that of the Fe-Al rock series with Longtan Formation (P₃l), especially Nb and REE. The Sc, Nb and REE concentration in the Fe-Al rock series is an outcome of combined action of the initial enrichment weathering and the late beneficiation reformation on the Emeishan basalt.