In Korea, due to the split systems between early childhood(EC) “education” and “care,” the required educational attainments and qualifications have differed between teachers of preschools and child care centers. These gaps likely leads to differences in process quality in classrooms, which suggests educational inequality from the early years of life. To address this problem, this study aimed to investigate the qualifications and educational attainments of EC workforce in the United States, which has also split EC systems both at the federal and state levels, and its recent efforts to reform relevant systems to strengthen expertise among the workforce. While EC teachers’ qualifications and levels of education have varied depending on the settings, sources of funding, and regions even within the same states in the U.S., the federal and state governments have taken initiatives to enhance the quality of the workforce by setting higher standards (e.g., bachelor’s degree) first for public programs, such as　public pre-K and Head Start, and by requiring in-service teachers to participate in professional development in order to renew their credentials every three to five years. Other efforts that state governments have made to improve the EC workforce’s educational attainments are as follows: a) aligning and coordinating curricula between two- and four-year institutions; b) expanding a bachelor’s degree program in two-year colleges; c) implementing the Credits for Prior Learning system; and d) providing financial incentives and scholarships. The implications of the U.S. case were discussed in terms of the professionalism of EC teachers in Korea.