Abstract: The research subject of this article is the regulatory and legal basis of the activities of Soviet trade unions regarding labor protection in 1985 - 1991. The author gives a description of the main formative stages of the unions' work. The article's aim is to give an idea of the ties between the regulatory-legal framework of the labor unions' activities concerning labor protection and the changes taking place in the country. To achieve this goal, the author pays particular attention to the state of the regulatory-legal framework at the beginning of the policy of Perestroika, namely, its integrity and its changes in 1987 - 1991 caused by a change in the country's domestic policy. The methodological basis of this study is founded on the principle of historicism. According to this principle, the regulatory and legal basis of labor unions' work in labor protection in 1985 - 1991 should be considered in close interconnection with the political and socio-economic processes occurring in the Soviet state. The author's general scientific method of synthesis made it possible to draw a picture of the presence or absence of a unified system of normative and legal acts of the labor unions' work in labor protection at various stages of the implementation of the Perestroika policy. The relevance of this work is determined by the fact that despite the existence of scientific interest in the analysis of the regulatory basis of labor unions in labor protection, the period 1985 - 1991 remains practically unexplored. The author introduces new historical sources into scientific circulation. Analyzing the data presented, the author presents a holistic view of the link between domestic policies and the changes in the regulatory base in labor protection and the deterioration of workers' position at the final stage of the Perestroika policy.