Abstract: In the process of metallographic teaching, grinding and polishing are two important processes that affect the quality of metallographic samples. The characteristics of microstructure of traditional bulk and non-bulk materials are analyzed in this paper, and the reason why the microstructure of non-bulk materials is easy to be damaged by grinding and polishing is pointed out. On this basis, the causes of four typical kinds of abnormal metallographic appearing in the experimental course of Aeronautical Materials in Civil Aviation University of China, such as “falling off type”, “rolling type”, “hole-growing type” and “adhering type”, were analyzed and summarized, and methods to solve the above-mentioned problems were discussed.