The article analyzes the situation of the Roman Catholic Church in Volhynia and Eastern Galicia in 1939–1941. The author discusses the Stalinist policy towards religion and the Church, forms and methods of government pressure on religious organizations, believers and clergy (intimidation, summoning for questioning, the introduction of high taxes, the use of a variety of administrative harassment, etc.). This paper shows the activity of the Soviet state security organs to the distribution of religious communities, to discredit priests and church leaders, as well as the persecution and repression against the most stubborn and rebellious priests. However, even such action could not undermine the authority of the clergy and tear items of local people on the maintenance of a constant tradition, and the Christian faith.