|Currently, most educators in Korea recognize that pedagogical content knowledge (PCK) is an important element of teachers` professionalism, and many studies of the factors that influence teachers` PCK have been conducted across education at all levels. PCK concerns how a teacher, based on his/her subject matter knowledge, transfers subject matter content to learners. In early childhood education in Korea, an integrated curriculum that combines two or more subjects is used. To implement this approach, most early childhood teachers seek to develop a range of pedagogical methods. However, it may be true that, in early childhood education (which emphasizes integrated, play-centered activities), teachers may have difficulty in acquiring sufficient depth of knowledge in each subject area. Therefore, one important task for early childhood teacher education is to help pre-service early childhood teachers establish the necessary foundation of knowledge. Early childhood teachers must have both subject matter knowledge and pedagogical knowledge in order to be successful. This article analyzes how three scholars, Dewey, Kilpatrick, and Bestor, addressed the issue of the relative roles of subject matter knowledge and pedagogical knowledge in teacher education. By analyzing the different positions of these three scholars, this article seeks to offer some insights that may help early childhood teacher education programs to prepare prospective early childhood teachers for success in their future professions.