This paper examines the role of the Organisation of Islamic Cooperation (OIC) dispute settlement mechanisms in addressing ethnic tensions in the Horn of Africa, focusing on how the OIC’s diplomatic tools, mediation practices, and conflict-resolution frameworks operate within one of the world’s most unstable regions. It analyzes how the OIC engages with member states and local communities to manage ethnic grievances, facilitate dialogue, and encourage peaceful negotiations, while also considering the organization’s limitations in enforcement capacity, resource availability, and political cohesion. The paper explores specific cases in the Horn of Africa to assess the effectiveness of OIC initiatives, including early-warning efforts, humanitarian diplomacy, and collaboration with regional bodies such as the African Union and IGAD. By evaluating both the strengths and challenges of the OIC’s involvement, the paper highlights how Islamic multilateral institutions contribute to conflict mitigation and the broader quest for stability in ethnically diverse and politically fragile contexts.