The study of geological fluids is a focus of earth science. The compositions of fluid inclusions are the key to understanding the geological fluids. In traditional methods, the anions of liquid ingredients are detected by single-channel ion chromatography, and the cations of liquid ingredients are detected by AAS or ICP-AES. The traditional methods can only analyze a few mineral species and requires a larger amount of mineral (over 3 g). The dual-channel ion chromatography was used in this study. After a number of condition experiments, the authors optimized the pre-treatment analysis method (such as burst and extraction), and identified the detectable ions in different minerals. The weight of the sample was reduced from 3 g to 300 mg by using the concentration method. Quartz, calcite, fluorite, sphalerite, garnet, magnetite and pyrite were analyzed for their liquid phase compositions (Li⁺, Na⁺, K⁺, Mg²⁺, Ca²⁺, F^-, Cl^-, Br^-, NO₂^-, NO₃^- and SO₄^2-). The new ion chromatographic analysis method established by the authors is characterized by such advantages as simple operation, rapidness, low cost, and requirement of only a small weight of sample, thus expanding the scope of analysis of mineral species. In addition, this method can provide more direct and effective information for the study of ore-forming fluids.