All instructors require to understand about their learner, to maximize the educational effect. From the educational psychology' s point of view, the category of understanding about the learners consists of two divisions, that is 'Development' and 'Individual Differences'. This paper is focused on the 'Individual Differences related to Anxiety', in the high school students majoring in korean traditional music (especially majoring in korean traditional string instrument called Kayakum). Further, it is schemed to maximize the effect of korean traditional music education. As a research method of this study, I have selected first of all 40 students as a sample, who are majoring in 'Kayakum' in traditional arts high school. After measuring 'Individual Differences related Anxiety' of a sample with 'STAI & TAI' by C. D. Spielberger, I have analyzed the correlation between ' Individual differences related to anxiety ' of a sample and their record of major practicalness test. Analysis showed that the high school students majoring in korean traditional instrument had various 'Individual differences related to anxiety', and had a deeper correlation between the 'Individual differences related to anxiety ' and the achievement of major practicalness test.