Abstract: The basis of using remote sensing data to extract the altered minerals is to know the spectral absorption characteristics of different altered rocks and minerals. In particular, we need to master the spectral variation characteristics of rocks and minerals in different physical and chemical environments. The Fangshankou area in Beishan has complex geological evolution history, where developed various types of altered rocks. So, what are the characteristics of spectral absorption characteristics of different rocks and minerals, and is it consistent with the spectral curves of the corresponding terminal elements on remote sensing images? In this paper, the related research has been carried out. The experiment results show that the spectral curve of outcrop rock sample and crushed stone samples are the most closely related to the standard sample. In addition, the desert varnish on the surface of the sample has a certain effect on the absorption depth of the spectral characteristic peak. However, the physical destruction of rocks cannot lead to changes of the spectral. By analyzing the spectral characteristics of typical altered rocks, it's found that the altered rocks in this study area contain alteration minerals with Fe²⁺, Fe³⁺, OH^-, CO₃^2- ions and groups. The remote sensing spectral curves of altered rocks and their measured spectral curves have roughly the same characteristics. However, due to the high similarity of the spectral curves of different altered rocks, it is quite difficult to identify the types of alteration rocks accurately and effectively by using remote sensing images only. These results will provide a theoretical guidance for the extraction of remote sensing altered minerals.