The article discusses approaches to the establishment of the international legal regime for the complete demilitarization of outer space. The existing regime of partial demilitarization of outer space, which does not fully guarantee the peaceful use of outer space, is described. The importance of adoption of the Treaty on the Prevention of the Placement of Weapons in Outer Space focusing on the concept of pre-emptive disarmament has been emphasized. The article proposes an attempt to assess the effectiveness and applicability of international legal means that in the future will contribute to the establishment of a regime for the complete demilitarization of outer space by analogy with the current Treaty on Open Skies (1992). The solution of the international legal problem of the arms race extension to outer space requires states to agree to additional political compromises, as well as to implement transparency and confidence-building measures concerning outer space. © 2021, Univelt Inc. All rights reserved.