The 21st century has witnessed a surge in global forced migration movements, rendering migration management one of the most critical areas of international politics and humanitarian governance. In this context, the United Nations High Commissioner for Refugees (UNHCR) plays a pivotal role as the normative and operational leader of the international refugee protection regime. This study analyzes UNHCR’s activities and cooperation mechanisms in the field of migration management through the case of Türkiye, the country hosting the largest number of refugees worldwide. The relationship between Türkiye and UNHCR, which began in 1960 and gained a formal legal basis with the 2016 Host Country Agreement, encompasses a multidimensional structure including registration, protection, legislative alignment, capacity building, and social cohesion. The paper examines the multi-layered governance model conducted by UNHCR in collaboration with the Presidency of Migration Management, ministries, local authorities, and civil society organizations. The findings indicate that the organization serves not only as a provider of operational support but also as a strategic partner guiding the alignment of Türkiye’s national migration policies with international norms. However, fundamental challenges such as the inadequacy of international burden-sharing, delays in registration processes, and rising anti-migration sentiments persist.