The purpose of this study was to deepen our understanding about the practical meaning of school readiness. The study was conducted through in-depth interviews of 8 preschool children, 3 mothers and 3 teachers. The findings of this study were as follows: First, teachers put emphasis on balanced cognitive and social development of a child as an important part of school readiness. And the children experienced inner conflict between practice being developmentally appropriate to the pressure of pre-learning. Second, mothers want their children to be prepared to be a student who to be students suitable for elementary school education, in the teachers' opinion. When their children are postponed from entering school, they felt they were not 'good mother'. Third, all children's concepts of elementary school and school readiness reflected opinions of their parents and their teachers. Most of them showed expectations and worries about entering school and they felt the pressure of pre-learning. Therefore it is necessary to come to an agreement about school readiness among policy makers, parents and teachers of preschool and elementary school.