NATO is the longest political and military organization in the contemporary history، which has redefined its missions in several stages since 1949 up to now. Having proposed a new concept for security in the second decade of the 21st century، this organization sought to protect the security of the Atlantic territory outside the region، and designed، and is now running، a number of mechanisms to legitimize this action. Dynamic attendance in various geopolitical regions contain NATO’ s most significant strategy. Due to this، it is regarded as the sixteenth neighbor of the Islamic Republic of Iran، which has physical presence all over the geopolitical regions of the country. In this regard، the identification of NATO strategies for expanding its geopolitical presence by focusing on the western borders of Iran is the main concentration of this study، which is trying to answer the essential question of how NATO is making an attempt to expand its territory in the geopolitical regions to the west of Iran. Following a descriptive-analytical method and using the library، internet and media data collection methods، the research mainly hypothesizes that NATO is trying to maintain and expand its sovereignty by the principles? ? of liberal democracy and the free market as the driving force of the contemporary world system. Making use of strategies of expanding the formal and informal political frontiers، humanitarian missions، defense and security cooperation، and extending its administrative and organizational offices، NATO is trying to extend its territories to the geopolitical regions of Turkey and Arabian regions to the near-western area، and extending its presence in the Black Sea، the Aegean Sea، the Mediterranean، as well as the North Africa in the far-western regions of Iran.