The importance of our research is that it examines the causes and sources of the security challenges in the internal security environment of the GCC countries, and aims to address the most important issues that are of great interest, namely, the issue of inter-GCC differences and addressing the issues of regional security for the Gulf region, After it is one of the most dynamic and more polarized areas for the emergence of threats and challenges because of the multiplicity of sources of threat and their complexity due to the specificity of the strategic environment and the negative repercussions it can have on the Gulf region, especially the issue of regional security of the Gulf Cooperation Council Which has become a magnet for competing international and regional powers to preserve their interests and ensure the achievement of their objectives. This has further complicated the internal security environment in the Gulf, especially the recent events represented by a package of measures taken by Saudi Arabia, the UAE and Bahrain. As well as Egypt against Qatar, have begun to reveal to us the depth and root of differences, the size of internal challenges and the weakness of the ability of the GCC countries to meet their obligations in laying the foundations of a joint security-defense system with the capacity to face these challenges collectively, Security challenges are therefore not only external regional or international, but internal with inter-GCC interface