This study discussed that teacher’s grammar and learner’s grammar can be distinguished from some grammar which we used. Also, we discussed the concepts and scope of teacher’s grammar and learner’s grammar. First, this study summarized the various terms and concepts related to grammar that we use, focusing on previous research. As a result, we can classify into 8 major grammatical terms and three major categories. And it is discussed that teacher’s grammar and learne’sr grammar can be set separately by these grammar. We proposed the structure of ‘Transformation of grammatical knowledge' and ‘Cycling process of grammar learning’ as reasons. Therefore, the teacher's grammar is conceptualized as ‘Grammar that can be directly or indirectly internalized to teachers or externalized by teachers', and the learner's grammar is conceptualized as ’Grammar that can be directly or indirectly internalized to learners or externalized by learners'. Also, as the conceptual scope of teacher’s grammar and learner’s grammar, teacher’s grammar is included in academic grammar, learner’s grammar is included in school grammar. And this study discussed the development of academic grammar to school grammar, school grammar to teacher’s grammar and teacher’s grammar to learner’s grammar.