Teachers are the most important factors in the education. Teachers have many roles in the circumstances of education. The roles of teachers are the guardian as a human, the co- worker as a colleague, the promotor of learning, the counselor of students, the researcher in teaching subject and so on. For these successful roles teachers should communicate with students well. But many teachers have never learnt some skill for better communication or speech in their teacher``s training courses. There are many speech styles and habits which students dislike. Those are inarticulate pronunciation, useless words, redundant expressions, indecent jokes, vulgar expression, rapid speech, difficult vocabulary, disregarding expression for student, difficult explanation and so forth. Speech of Teaching is the teacher``s communicative activity with the students for the delivering the knowledge in the classroom. Same text, subject and syllabus show different effect and result according to the communicative skill of teachers. Democratic teacher is a leader, has grace, seeks to persuade and encourages the students, helps students to decide some problems autonomously. Language of teaching has many aspects: preliminary language, introductory language, agreement language, contents language, objective language, motive language, explaining language, question- answer language and finishing language. Teachers should use the standard common language, efficient nonverbal language and proper paralanguage that is body communication (face, eye contact, gestures, posture, walking, clothes, chronemics(time) and proxemics(space). All students should learn and practice the language skill of teaching in college of education, and also all teachers should study and training the skill of teaching unceasingly.