Children entering elementary school require considerable transition support from parents and teachers. However, most studies on preschool-elementary school transition have focused on Western contexts. Therefore, this study investigates children's perceptions of elementary school in South Korea before and after entering school. The study sample comprised 160 participants, including 84 five-year-olds and 76 first-grade students enrolled in preschools and elementary schools in Seoul, Gyeonggi-do, Daejeon, South Korea. As part of the research methods, children were asked to draw pictures and describe their elementary school; in-depth interviews were also conducted to understand their perceptions of elementary school. The study results are as follows. First, children showed positive perceptions of elementary schools concerning "relationship building with new friends," "acquiring new knowledge," and "interest in new activities," and negative perceptions, such as "mental pressure to follow the rules," "being scolded by scary teachers for doing something wrong," and "burden of learning." Second, perceptions of elementary school differed by age: six-year-old children showed a lower "burden of learning" and higher "interest in new activities" than five-year-old children, showing that six-year-old children who experienced elementary school enjoyed the new activities conducted at the school instead of experiencing the burden of learning. Accordingly, this study proposes the need to provide proper information about elementary school practices and ensure cooperation between preschools and elementary schools to promote optimal learning that supports young children's holistic development to prevent prejudices against elementary school.