The study aims at characterising four bacterial infectious agents listed on the CDC A list, i.e. Anthrax (Bacillus anthracis), plague (Yersinia pestis), botulism (Clostridium botulinum) and tularemia (Francisella tularensis) as potential tools used in a bioterrorist attack causing diseases. The paper also includes information on their occurrence in Poland and the EU. Despite the real threat of terrorism in the 21st century and large-scale activities aimed at limiting the occurrence of this phenomenon, it should be borne in mind that pathogens listed on the CDC list A, although spotted primarily in animals, can be a real threat to people’s health and life. Among the discussed microorganisms, only Francisella tularensis and Clostridium botulinum cause sporadic diseases in Poland; however, it should be remembered that both Bacillus anthracis, occurring in Europe, and Yersinia pestis, occurring in Asia and Africa, can pose real threats to human health and life not only in natural infections, but when used as a biological weapon.