Abstract: Coal petrology analysis is widely used in coal facies research, geological exploration and coal blending test. Qualified polished coal slice is the premise of coal petrology analysis. In order to solve the preparation problem of special coal optical plates, such as brittle samples and aging coal optical plates, a complete preparation process was raised, and the feasibility of the process was verified. The results showed that R_max was very little affected by secondary preparation, but the maceral group composition content was significantly affected, and the fluctuation of the anthracite' microcomponent was the greatest. When the maceral group composition quantification of the aged special coal polished slice, attention should be paid to distinguishing between the vitrinite and intertinite of anthracite, and to increasing the test number of the bituminous coal' optical plates, to reduce the effect of the coal' heterogeneity on the results.