The complexity of threats to all social, economic, political, and even cultural segments of the world in the 21st century has introduced various mechanisms for national security. One of the most important factors in this process is the structural transformation of the military in order to eliminate the inefficiencies of the conscription military system. Therefore, the coordination of the Islamic Republic of Iran's defensive and military system with the prevailing patterns in the international system was the main concern of the researcher and the main focus of the research was to provide the national security of the Islamic Republic of Iran through the transformation of military service from conscription into a professional military. For scientific explanation of this issue, the question arises as to how it is possible for the Islamic Republic of Iran to transform the defensive power from conscription into a professional military? The present research is a mixed-exploratory research. Data collection was done using library and field method. The research population is researchers, specialists and experts in the areas of military and defense, the faculty members of the strategic studies centers of countries with professional military, and experts in defense management in different countries; In order to analyze the findings, quantitative and qualitative analysis was used in both library and field information sections. Finally, four scenarios in the period of 1400 to 1420 were arranged about the process of the transformation of military service from conscription into a professional military.