This study was to purpose to draw on implications for Korean education in relation to 21st century key competencies by investigating the case of Japan. In particular, with focus on mother tongue education, this study seek to discover how the discourse of key competencies dialogued/dialogue with traditional discourse of school education(i.e. educational policy, curriculum and evaluation) in Japan. What the research questions of this study were 1) what procedure of competency education are for Japan and what lessons from them are; 2) what is the country-level assessment of key competencies in detail and what possibilities and limitations are of them; 3) In regarding appropriation of the notion of key competencies, what would be future directions for competency education and assessment in school. Consequently, for the future directions for 21st century education with focus on key competencies, this study suggested the followings: In more autonomous stance, the discourse of key competencies as global direction of education should be delved into and dialogue with Korean traditional school contexts. Educational stake holders needs for the long- term and deliberation to make decision with evidence basis.