A total of 186 early childhood teachers from South Korea and U.S. participated in this cross-cultural comparison study examining their beliefs and practices to support children’s social competence. Participants completed an instrument specifically designed to measure early childhood teachers’ beliefs and practices of using environmental, natural activity, and intensive instructional strategies to support children’s social competence. Results found some similarities among South Korean and U.S. teachers that they both believe in and practice environmental, natural activity, and intensive strategies in the respective order from the most to the least. Results, however, also found some culture-specific differences that U.S. teachers rated all the strategies higher than South Korean teachers, and that stronger relationship between beliefs and practices were found among South Korean teachers. Sociocultural factors related to early childhood teachers’ beliefs and practices about supporting children’s social competence are discussed.