Today, unity and cooperation in international relations are of great importance due to the extensive communication between countries and the globalization process. The Caspian Sea is very important in maritime transport. The seabed network is located between its major ports, and each of these paths is of particular communication and economic importance to the countries of the sonnet Securing shipping lines is one of the naval tasks of any country that may be carried out in the form of military cooperation between the countries of the sea .The purpose of this natural research is the cooperation of the Islamic Republic of Iran with its neighbors. Military Interaction Practiced in Securing Shipping Lines in the Fields of TerrorismThe data of this study were analyzed at both qualitative and quantitative levels. In the qualitative analysis section, using the documents and interviewing with 5 Iranian Navy experts, the questionnaire was prepared and between 2 The senior officers of the 4th Marine Corps of the Islamic Republic of Iran Army were distributed Two methods of Friedman ranking analysis have been used to determine the importance of Iran's military cooperation with the Caspian neighbors And because the hypothesis is not considered for this research, the research goals were investigated and finally accepted In the end, it was determined that military cooperation in three areas of maritime interactions Creating a collective security structure and combating terrorism could be important in securing shipping lines in the Caspian Sea.