The purpose of this study is to discuss changes in the national security paradigm and countermeasures for national intelligence activities. This study was conducted as a literature research method through analysis of domestic and foreign media reports, research reports, and related prior studies related to national security and transnational security threats, and National Intelligence Activities. As a result of this study, changes in the national security paradigm include: 1) the emergence of various security threats due to globalization and the intensification of transnational security threats such as weapons of mass destruction, cybercrime, terrorism, drug trafficking, environmental destruction, and the spread of infectious diseases; 2) the characteristics of transnationality, potential, tough measurement, and connectivity; 3) The level of transnational security threats is likely to continue to expand and increase in the future. In order to respond to national intelligence activities, it is necessary to: 1) diversify the security targets for information collection and to readjust the national information target priorities; 2) need for comprehensive and flexible information and counterintelligence; 3) strengthening the comprehensive analysis function of national information; 4) it was suggested to strengthen cooperative security activities based on close cooperation between actors. Finally, the limitations of this study and suggestions for future related studies were discussed.