This research article explores the issue of the formation of international legal principles on the prevention of the placement of weapons in outer space (1959-1979). The historical prerequisites and main provisions of key international treaties related to this issue are analyzed. The gradual formation of key agreements in the context of political confrontation and mistrust between the leading space powers, which is considered in the research, was an important step in limiting and containing the arms race in outer space. The article also discusses the limitations and gaps of the main agreements of international space law and related agreements, which only partially regulate the military use of space and do not address new types of weapons and technologies that can be deployed or used in outer space for military purposes.
 The article suggests that one of the ways to strengthen the international legal framework for outer space demilitarization is the development of new international agreements that would prohibit the proliferation and use of such weapons and technologies in space, and that would protect outer space from aggressive military activities. Moreover, the article justifies the importance of the international legal regulation of the military use of outer space as a tool for preventing an arms race in outer space. It can include such issues as regulation of new types of weapons and their deployment that are not prohibited by main international agreements of international space law and ensuring the peaceful use of outer space.
 The article also presents an explanation concerning a concept of «weaponization of space», which is part of the military use of space. In this vein, it evokes the necessity of further strengthening of the international legal regulation of the discussed topic.