Abstract: Extraction of alteration mineral information plays an important role in prospecting of mineral deposit. Nowadays, using multi-spectral remote sensing data for extraction of alteration mineral information has been developing rapidly. The methods of extraction of alteration mineral information include optimal PCA (Principal Components Analysis), band ratio, SAM (Spectral Angle Mapping), etc. This paper has choosed Duolong area, Gaize, Tibet as the study area and Duobuza porphyry copper deposit as the typical deposits, and adopted several methods for extraction of alteration mineral based on ASTER remote sensing data, then the result of each method has been compared. It avoids the restriction of each method, and provides more accurate remote sensing evidence for detecting mineral deposit.