article is devoted to the consideration of the activities of the Prague Group of the Ukrainian Party of Socialist-Revolutionaries (UPSR) on the creation of an association of socialist forces of the USSR in emigration – the Socialist League of the new East. This organization was supposed to prepare the ground for the formation of an alliance of the peoples of the USSR after gaining independence. party tried to implement it from the beginning of the 1920s, consolidating in Prague groups of Belarusian and Russian socialist-revolutionaries. main thesis of this article is that the Prague group of the UPSR played an important role in the creation of the Socialist League of the peoples of the new East.The Prague group of the UPSR has developed the concept of a possible unification since the early 1920s. In particular, in 1921, one of the leaders of the UPSR N. Hryhoryiv held a public debate The National Question in East Representatives of the majority of the socialist parties of the peoples of the USSR abroad took part in it, they demonstrated their vision of interethnic relations in Eastern Europe and the possible unification of these peoples in the future for the common defense of state, economic and cultural interests. leaders of the UPRS M. Shapoval and N. Hryhoryiv considered the consolidation of the socialist anti-communist forces of Eastern Europe is an important contribution to the destruction of the USSR and the Bolshevik government, its discredit on the international scene. At the same time, they believed that just socialist forces (very popular at that time in Europe and the world) could have become the basis for the unification of the Soviet Union after its collapse into a new alliance. That is why they made efforts to unite socialists in emigration.The UPSR reached agreements with Russian and Belarusian socialist-revolutionaries in Prague, have established contacts with the other socialists of the USSR and have created in 1925 the Union of the Peoples of Eastern Europe. Аs a result of its transformation in October 1926, the UPSR with the other socialists of the USSR created the Socialist League of the new East (initially the organization was called the Socialist League of the Peoples of the East). As a strategic goal of the Socialist League of the new East it was proclaimed the creation of a confederation of independent on the territory of the USSR – the free alliance of new national states – in the composition of Russia, Ukraine, Belarus, Georgia, Armenia, Azerbaijan, Uzbekistan, Turkestan and, possibly, the Caucasian republics, mutual guarantees of inviolability of borders and rights of national minorities; economic and financial cooperation, in particular customs and tariff union.Therefore, the Prague group of the UPSR played a significant role in the creation of the League. It was a unifying center for the consolidation of the socialists of the USSR in emigration, and its leaders contributed greatly to the organization of the League and the creation of a program that corresponded to the party tasks of the Prague Group of the UPSR.