This research is aimed at examining the improving methods of teacher education through researching what teaching difficulties in Korean language class are exist. In this paper, we have examined the types of difficulties in the teacher's Korean language class through the searching flame which is called 'Teaching difficulties in Korean Language Class.' The occurrence context and caution of the difficulties according to each type and the teacher's responses were explored through qualitative case studies. We have found that the difficulties of teacher's Korean language class include 'Open Difficulty', 'Blind Difficulty', 'Hidden Difficulty', and 'Unknown Difficulty'. From the analysis of difficulty types of Korean language class, we proposed improve method for time, form and content of teacher education. In the meantime, development plans for improving Korean language class and teacher's professionalism have been studied in theoretical perspectives. This research, however, provide meaningful proposal of improving plan for teacher education based on the real difficulties in the class and teacher's knowledge.