This paper has examined what senior high school teachers should know about teaching how to listen and how they should do it. How they should teach listening is not described in the Course of Study for Senior High Schools. It is just described that one of the contents of a subject Communication English I is understanding information, ideas, etc., and grasping the outline and the main points by listening to introductions to specified topics, dialogues, etc. And also, in order for the language activities to be effective, the following should be considered for instruction: drawing students' attention to such phonetic features as rhythm and intonation, and to the speed and loudness of connected speech when listening to or speaking in English. However, how to teach listening as well as what is listening is not explained in detail, and what is worse, not any examples of how to teach listening are not given in the Course of Study. And listening activities are not conducted in many classrooms of senior high schools. The authors are going to explore the difficulties of both listening and teaching listening, referring to several course books of English teaching in this paper, and in the next paper, which will be published next year, they are going to survey senior high school teachers on actual situations of teaching listening in their classrooms and to clarify good listening activities and propose that teachers should use them effectively in their classrooms.