This article examines the policy of national-territorial delimitation of the Turkic peoples in Central Asia during the 1920s–1930s within the framework of Soviet national policy. The author analyzes the historical and ideological prerequisites that led to the division of the unified cultural and ethnic space of the Turkic peoples into separate national republics. It is shown that the main goal of the Bolshevik authorities in this policy was to establish control over the region, weaken Pan-Turkist and Pan-Islamist movements, and create formally equal but centrally subordinate national entities. The delimitation disrupted traditional interethnic relations, contributed to the strengthening of ethnic self-awareness, and caused ethnic tensions and crises, especially in border areas. The administrative boundaries established during the Soviet period later turned into the state borders of independent countries and, in the post-Soviet period, became a source of territorial disputes and interethnic conflicts. The article analyzes the problems of ruptured historical ties among related peoples, the formation of artificial ethnic identities, territorial disputes, and ethnic contradictions that persist to this day. In addition, the impact of national-territorial delimitation on the formation of the borders of modern independent Central Asian states is explored. Based on archival sources and contemporary studies, the author demonstrates that delimitation was an important part of the USSR’s colonial governance strategy. This work is intended for historians, political scientists, and regional researchers.