Our ancestors made the brilliant achievements in studyingCharacter structure in Ancient China, which laying the foundation for today’s research. From Han to Qing dynasty, the achievements of Characterstructure study mainly are: First, realized the importance of Characterstructure; Second, improved the systematical theory about Characterstructure: 1. The theory of grapheme constituting character. 2. Thehierarchical structure theory about Character. 3. The theory of thegrapheme having different functions. Third, made a substantial researchabout Character structure: 1. The research about the character. 2. Theresearch about the grapheme. 3. The systematical research about the whole Chinese Characters. But these researches had some shortcomings: not making concepts distinction between “ radicals ” and “ Chinese character component”; lacking of the character’s formal structure research, and so on. In ancient China, we had already constructed the systematical theory about character structure, this fact is helpful to correct the mistake about the claim that “in ancient china, there was no scientific theoretical system of philology”.