The argument of National security and its protection is one of the main duties of the States. Security itself has such a valuable situation among the States that it is called as the High politics. Preserving and maintaining security is an irrefutable necessity for all the States and for all the different forms of governments, so that, for the states, the lack of. Security is equal to lack of national life, land and population. Meanwhile, the conception of national security is of the most important ones. This conception will be easily grasped and outspreaded by the different governments and the governments can justify their actions under the title of national security. Professor Bary Buzan believes that national: "security is a case concept and it depends upon the particular time and place, and will be appeared for every government as its own special form. Hence, the main question that can be raised is that wheter, the National Security, as is put for the Nation - States which emerged from Westphalia, can also be proven applicable for the third world countries which often have passed the process of Nation - State building rather imperfecty - or not?!Another question that can be put here is that whether the national security in the third world states as (it) was conceptualized during the cold war, has the same application after the cold war or not?! In response to the above questions, it should be said that the national security in the third world countries during the cold war was influenced by relations and competition of the two super powers. Hence, hardware aspect of security has had more application. But by the end of cold war, and the collapse of USSR, software aspects of security such as economic, bio - environmental and demographic aspects are addressed more.Therefore, it should be said that after the cold -war time, especially after the September 11 (2001) event, in the third world countries, security could be considered as a return point in the international interactions realm. and it got more internal consideration and dimension than external. Hence, what is considered as threat for the national security of the countries has its root in the internal structure, and not in the external elements, and perhaps in the structure emerged from the illusive mind.