The theorists of the regional security complex belive that this complex is always conflict-prone based on a pattern of enemity relations due to three components: its being a conflict hotspot, its securitization of issues, and its special regional security context. It is for this reason that we have been winessing a pattern of enemity relations in deferent periods of time. After the 11 September attacks, when the terrorist groups were formed in the West Asia region, there occured a change in the pattern of enmity relations. The present article aims at generating a proper unserstanding of the effect of terrorism in changing the pattern of enmity relations in the security complex of West Asia. How has terrorosm managed to change the pattern of enmity relations in the West Asia? The method being used in this research is descriptive-analytical and the method of data collection is library and internet as well. One of the most important findings of the present research is that although the military-type pattern of enmity relations has been extracted from terrorism, the phenomenon of terrorism has been made by the hands of foreign powers outside the region such as the United States and inside the region such as Saudi Arabia and the Zionist regime for balancing policy in the face of the Islamic Republic of Iran. As long as the countries of the region operate on the basis of the realsim paradigm and the Security Dilemma, they will not be able to resort to regional alliance in order to eliminate in the face of a few phenomena like terrorism. It follows that in order that a pattern of amity relations be formed, we are in need of the formation of regional alliances and elimination of religious and ideological differences.