Bioterrorism is one of the main public health categorical domains. According to sociological analytics, in postmodern society terrorism is one of the real threats of the 21st century. While rare, the use of biological weapons has a long history. Recently, anthrax has been evaluated as one of the most dangerous biological weapons. Naturally occurring anthrax in humans is a disease acquired from contact with anthrax-infected animals or anthrax-contaminated animal products. Usually anthrax infection occurs in humans by three major routes: inhalational, cutaneous, and gastrointestinal. Inhalational anthrax is expected to account for most serious morbidity and most mortality. The clinical presentation of inhalation anthrax has been described as a two-stage illness. Many factors contribute to the pathogenesis of Bacillus anthracis. Antibiotics, anthrax globulin, corticosteroids, mechanical ventilation, vaccine are possible tools of therapy. Smallpox existed in two forms: variola major, which accounted for most morbidity and mortality, and a milder form, variola minor. Smallpox spreads from person to person primarily by droplet nuclei or aerosols expelled from the oropharynx of infected persons and by direct contact. In the event of limited outbreak with few cases, patients should be admitted to the hospital and confined to rooms that are under negative pressure and equipped with high-efficiency particulate air filtration. In larger outbreaks, home isolation and care should be the objective for most patients. Progress in detection, suitable vaccines, postexposure prophylaxis, infection control, and decontamination might be serious tools in fight against the most powerful biological weapon. To assure that the public health and healthcare system can respond to emergencies, the government should direct resources to strengthen the emergency-response system, create medication stockpiles, and improve the public health infrastructure.