Abstract:National critical technologies are crucial to economic prosperity, social welfare, and national security of a country or region, playing a vital role in enhancing national scientific and technological innovation capability and boosting its international competitiveness. How to identify and select national critical technologies is the prerequisite and foundation for optimizing research layouts and cultivating priority fields. Based on the understanding of the connotations and characteristics of national critical technologies, this study proposes an analytical framework for their identification and selection. Through a cross-case analysis of practices in the United States, the European Union, South Korea, and Australia, the study compares the commonalities and differences in their criteria, methods and procedures, organizational mechanisms, outcomes, and applications. This findings offer empirical insights and important implications for China in advancing the identification and selection of national critical technologies.