The purpose of this study is to investigate the background. aim, key element and effect of microteaching as a powerful technique to improve the quality of teacher education. Microteaching was developed at Stanford University in 1963 as a kind of competence-based teacher education. Microteaching is a highly scaled-down sample of instructional system in many ways-time and content of instruction, class size. number of students and teaching skills etc. It is a kind of simulated form of teaching. It is recognized as an effective technique to improve teaching behavior and the ability of classroom management-the main purpose of instructional suprevision. Applying systems approach and the principle of learning by observation and modeling, it affords both pre- service and advanced teachers an excellent opportunity to improve or develop specific teaching skills and new instructional strategies. And it provides the opportunity for the apprenticeship and meta- learning experience. Many practitioners of microteaching laboratories assumed that mastery of particular skills in a microteaching situation will enable the teacher Lo use them automatically when necessary in regular classroom interactions. The needed equipments for microteaching are video (or audio) tape recorder, TV camera, and microphone etc. Instructional processes are recorded mainly on videotape to review, analyse and refine. The trainee can see the replica immediately after the lesson. The key elements and procedure of microteaching are summarized as follows: instructional planning(teaching skills, size and object of class, time. content etc.), instruction, feedback and evaluation, re-instruction. As a result of research on the effect of microteaching, it is reported that microteaching has a positive effect on teacher's cognitive and affective domain. So, to facilitate the professionalism of teaching and scientific teacher education, the positive interest and research about microteaching is needed.