This study investigated the relationships of students' self-educational ability in their college age with their personal teaching theory (PTT) in their high school age. A total of 789 students completed two kinds of questionaires, one of which was to measure their selfeducational ability (interest in learning subjects, self-directed thinking, skillfulness of learning method, self-monitoring, planning, independence, and self-actualization) in their college age and the other was to measure their personal teaching theory in their high school age. The major findings were as follows: (1) The students who wished to go on to higher level of education in their high school age showed more self-educational ability than those who did not wish to go on to higher level of education, and (2) the personal teaching theory of the students who wished to go on to higher level of education was more acive and self-regulational in their high school age. These results were discussed in relation to how to foster the self-educational ability of students.