National Security Act may refer to:
National Security Act, 1980, an Indian law to provide for preventive detention National Security Act (South Korea), regarding seditious activities National Security Act of 1947, a United States law that established the Central Intelligence Agency National Security Act 2017, a Canadian act National Security Act 2023 (c. 32), a UK act strengthening laws against espionage, political interference, sabotage, and assassination
National Security Law may refer to:
National Security Law of the United States National Security Law of the People's Republic of China National Security Laws of China's Special Administrative Regions, i.e.: Macau National Security Law 2020 Hong Kong national security law National Security Law (Brazil)