The geopolitical dynamics of Southeast Asia in the modern era are very complex, covering various factors such as economics, security and international relations. This area is known as a strategic point considering its location between the Pacific Ocean and the Indian Ocean, as well as important trade routes such as the Malacca Strait. One of the main aspects is the shift in global power, especially China’s increasing influence. The Belt and Road Initiative (BRI) has sought to build infrastructure in Southeast Asian countries, which offers attractive investment opportunities but also raises concerns about economic dependency. Countries such as Malaysia, Indonesia and Thailand are starting to rethink their strategies to maintain sovereignty while exploiting the growth potential of foreign investment. On the other hand, the United States is still trying to maintain its influence through strategic partnerships and defense programs involving regional countries. Programs such as the Indo-Pacific Strategy encourage alliances to balance China’s power, focusing on security and trade cooperation. In addition, ASEAN (Association of Southeast Asian Nations) plays an important role in creating diplomatic forums that facilitate dialogue between major countries. Maritime security is also a central issue, especially regarding territorial disputes in the South China Sea. China, which claims almost the entire South China Sea, is at odds with claims made by ASEAN countries such as Vietnam and the Philippines. These tensions often lead to military escalation of one of the parties, creating the risk of greater conflict. The expansion of China’s military bases and warship activities are felt to threaten regional stability. Countries such as Indonesia and Malaysia are seeking to improve their defense capabilities, including through modernizing their armed forces and strengthening military cooperation. The increased defense budget provides an impetus for the development of more effective defense strategies. Apart from that, domestic issues also play a role. Internal issues such as corruption, public dissatisfaction, and economic challenges can affect political stability. Countries like Myanmar face significant challenges, with internal conflicts pointing to weaknesses in governance. This crisis not only affects national security, but can also have regional impacts, considering the interconnections between countries in Southeast Asia. Socio-cultural dynamics in Southeast Asia also influence geopolitics. Globalization is bringing rapid changes in society, where issues such as national identity and human rights are starting to receive more attention. Social movements demanding government reform and transparency are growing rapidly, pushing the government to better respond to public demands. In this constellation, the role of media and information technology is very significant. Social media facilitates more open lines of communication, allowing people to voice their opinions and demand accountability. However, on the other hand, the use of information by foreign actors to influence public opinion is also increasing, adding a new layer of challenge. Overall, Southeast Asia’s geopolitical dynamics in the modern era reflect a complex interaction between global power, regional security, and interrelated domestic issues. This region will continue to be in the spotlight of world attention, with various opportunities and challenges that must be faced by its member countries in an effort to achieve stability and prosperity.