This study empirically demonstrated the effect of transformational leadership on teacher commitment. Recognizing the problem of research design of the preceding researches that reported the positive effect of principal\'s transformational leadership on teacher commitment, this researcher statistically separate the effect of transformational leadership into two parts: the real effect and teacher-perceived effect.
The final sample size of this study was 98 schools and 2,900 teachers. The analysis of the empirical data was carried out through the Hierarchical Linear Model(HLM 6.02 for window).
According to the result of the analysis, how teachers perceived principal\'s transformational leadership has statistically significant relationship with the level of their commitment to teaching, student, and organization, but principal\'s real transformational leadership has some restricted effect in causing teacher commitment. That is, while principal\'s real transformational
leadership have a significant effect on teacher commitment to organization, it has no significant effect on teacher commitment to teaching and student. This result of analysis imply that it is necessary to research the new theories of leadership in educational organization.