This paper tried to make clear the factors leading the classroom discourse with the continuous interaction between a teacher and learners focused on smooth communications through the analysis of classroom discourse in KFL(Korean as a Foreign Language) class. It was confirmed again that in order to lead smooth communications in KFL class, the role of the teacher is very important. Among others, it was found that the topic of the class schemed out by the teacher, the aspects of teacher’s response, teacher’s class operation etc affect significantly on the interactions among the participants of the class. It was cleared that regarding the topic of the class, the first important factor affecting the interaction, the selection of it attractive to the learners and the proper alteration of such a topic cause the smooth communication between the teacher and the learners. Next one is the aspect of teacher’s response against the learners’ response after teacher’s initiation to be identified that the teacher’s nonverbal response cause the positive feedback from learners to encourage their desire of speech to lead them to continuous interaction. In addition it was ascertained that the disconnection of the interaction was overcome by helping them in a verbal response with teacher’s provision of various scaffolding for the learners not only to find and correct the errors for themselves but to speak. Lastly the pattern of turn-allocation which is the essential factor for verbal discourse enabling all the learners to participate in the classroom discourse by turning equal allocation to the various learners and adjusting the order of speech with the consideration of learners’ character, was recognized as a way to promote the interaction.