This study investigates the influence of supercritical CO2 (scCO(2)) injection on minerals in high-rank coal under the temperature, pressure, and hydrologic conditions of a deep coalbed. A typical high-rank coal reservoir in the Qinshui basin, the #3 coal seam, is the focus of this research. A coal-scCO(2) geochemical reaction experiment is conducted to simulate the 2000 m burial depth of the coal seam. Field emission scanning electron microscopy is used to determine the locations of specific minerals and observe the effects of scCO(2)-H2O on these minerals at the micrometer scale. These results are combined with Xray diffraction and inductively coupled plasma-atomic emission spectrometry and mass spectrometry analysis results, and the effects of the scCO(2)-H2O fluid on minerals in the high-rank coal over a short period are discussed. In addition, the influence on coal reservoir structure was studied based on intrusive mercury and liquid nitrogen adsorption experiment. The results suggest that instantaneous CO, injection can provide a large amount of H+, and the initial ion release rate is high. Because of differences in mineral dissolution rates, scCO(2)-H2O has the strongest effect on calcite, followed by dolomite, aluminum hydroxide minerals, chlorite, and albite; however, effects are not obvious for illite, kaolinite, and quartz. Because of the low mineral content of the coal and the short experimental period, independent secondary carbon sequestration minerals did not form. However, the surface of aluminum hydroxide minerals reached partial dissolution equilibrium, and new layered aluminum silicate minerals were generated. The dissolution of carbonate minerals, albite, and chlorite increased the pore volume of the coal reservoir and improved the permeability of the samples. New layered aluminum silicate minerals and the chlorite with new occurrence increased the surface areas of samples after the reactions. After the reaction, porosity, pore volume, and surface area of the sample were greater, which also confirmed the positive transformation effect of the mineral changes on the reservoir.