To characterize the microcomponents and pore structure of high-rank coals under supercritical CO2 pulsation, the effects of supercritical CO2 pulsation on the mineral composition, organic functional groups, pore structure and pore fractal characteristics of high-rank coals were investigated on the basis of a combination of X-ray diffraction (XRD), Fourier transform infrared (FTIR), high-pressure mercuric pressure, low-temperature liquid nitrogen, and low-field nuclear magnetic resonance experiments. The results showed that after supercritical CO2 pulsation, the mineral compositions and organic functional group contents of the coals changed to different degrees, among which the contents of calcite, ilmenite and illite decreased, the contents of ferro-dolomite and kaolinite increased, and the characteristic peaks of oxygen-containing, benzene-ring-five-substituted H, and aliphatic functional groups decreased. The pore and fractal structure of the coals after supercritical CO2 pulsation was significantly altered, the total pore volume of the coal body increased by 188%, the percentage of seepage pore volume increased by 13 times, and the porosity increased by 8.272%. The fractal dimensions of the coal samples after supercritical CO2 pulsation all showed a decreasing trend, and the complexity of their pore structure and surface roughness decreased.