This article examines Cross-Border Armed Groups and Sovereignty Challenges in the Ugandan-South Sudanese Borderlands: An African Union Perspective with a focused emphasis on Uganda within the field of Political Science. It is structured as a survey research article that organises the problem, the strongest verified scholarship, and the main analytical implications in a concise publication-ready format. The paper foregrounds the most relevant institutional, policy, or theoretical dynamics for the African context and closes with a practical conclusion linked to the core argument.