Background: Bioterrorism is considered one of the recent global threats. Nurses should be ready because they are one of the first lines facing that. Aim: To examine the effect of an educational program on nurses' awareness regarding bioterrorism preparedness. Design: A quasi experimental pre/post-test research design. Setting: General Medical Center and Health Care Unit in Sakhaa, Kafr El-Sheikh City. Sample: A sample of convenience of 50 nurses. Tool I: A structured interview questionnaire in two parts. First part: Nurses' personal data. Second part: Nurses' knowledge regarding bioterrorism preparedness Tool II: Bioterrorism preparedness behavior and practices reported checklist included two parts. First part: Nurses reported behaviors during bioterrorism attack. Second part: Nurses reported practices during bioterrorism attack. Tool III: Nurses' bioterrorism management awareness scale. Results: 50% of nurses were in the age of 20-30 years, with mean 28.35±7.92 years. The good level of knowledge improved from 8% pre to 64% post program, the satisfactory reported behaviors and practices total score improved from 24% pre to 86% post program, and the high level of awareness improved from 16% pre to74% post program with a significant difference between the two phases of study at p≤0.001. Conclusion: The nurses' knowledge, practice and awareness regarding bioterrorism preparedness had improved after exposing to the educational program compared to their pre-program levels. Recommendations: Periodical up to date programs for enhancing the nurses` knowledge and skills about bioterrorism preparedness. Conducting larger risk assessment and disaster management plans in all health care organizations.