Bilateral relations with the State Library of the USSR named after V.I. Lenin occupy a special place in the post-war activities of the National Library of Poland in Warsaw. Based on common ideological positions, they gradually, starting with the ever-expanding book exchange, covered all areas of library activity, as well as joint scientific research. One of the areas of these interests was the widely understood history of the book and libraries, the study of the place of the book in modern cultural and scientific contacts of both peoples - Polish and Soviet.