With the Yulin Prefecture in China as the research area and the mineral compositions and reflectance spectra of 119 samples collected in the research area as research data, the present paper analyzes the correlation between the carbonate content of surface altered minerals caused by oil and gas microseepage and such charactersitic parameters of depth, width of its spectral absorption peak, establishes and evaluates a method for determining carbonate content, and proposes a new method for characterizing the degree of oil and gas microseepage by using the carbonate content. Research results show that this method is not only suitable for characterizing the oil and gas microseepage degree of carbonates, but also suitable for studying the oil and gas microseepage degree of other types of altered minerals. Therefore, the method can provide reference for studying oil and gas exploration technology by using spectral information of hyperspectral remote sensing.