The purpose of this study is to explore the understanding and awareness of IB curriculum operation to parents of domestic international schools. For this purpose, the study conducted interviews with parents and analyzed the results. In particular, it was intended to find out what parents felt about the learning process that their children, who were bilingual learners, experienced while participating in the IB curriculum program. As a research content, a brief understanding of the bilingual learner and IB curriculum, the core concept of this research, and later the research method for the study on the perception of IB curriculum operation felt by parents were presented. The data collections and in-depth interview execution were carried out. I analyzed the results of the interview and how the IB curriculum was being attempted at our educational site and the parents' perception required in the process of settlement. Through the actual PYP case of international schools where a combination of IB curriculum and national education curriculum are implemented, and through the consideration and suggestion of parents, IB curriculum gave implications for the revision of our national curriculum and the attempt of new curriculum. The results of this study will contribute to establishing the curriculum of bilingual students, which is characteristic of international schools, and to developing compliance with the exploration and application of teaching methods.