China and the US have responded to the challenges of a knowledge-based society, technological advancement, and global competition by implementing educational reforms to impart skills or competencies required of 21st century students. This study compares the rationales, content, and curricula design of both countries' key competencies frameworks and explores the possibility of reciprocal learning. Although their frameworks have certain similarities, significant differences have arisen due to cultural factors. The Chinese framework follows the Confucian tradition, emphasising moral education, political inclinations, transferring general competencies to specific-subject ones, and integrating key competencies in the national curriculum. The US framework follows the pragmatic tradition, emphasising generic skills and economic needs. Some US states have attempted to revise curriculum standards or incorporate 21st century skills by identifying their alignment with Common Core State Standards. Both frameworks have deficiencies and face challenges in implementation, and they can learn from each other.