The Library of the Institute for Western Affairs was established in 1945. Over the last 60 years, it has built a specialized collection of publications devoted to German and European Studies, as well as unique archives and press documentation. The Library is accessible to the general public; however, the resources are mainly used by students, researchers and journalists. Alongside providing access to its holdings, the Library also offers a range of academic information services.

The principles underlying the holdings’ build-up have reflected the Institute's research interests. The Library's initial acquisitions pertained to German history (esp. post-1870), as well as the Polish-German and German-Slavic relations up to the Second World War. In the first decade after the War, due to the changes in the boundaries of Poland, a sizable collection was amassed of publications relating to the heritage of the Northern and Western Lands, i.e., Silesia, Wielkopolska, the Lubusz Land, Pomerania, Warmia and Mazuria. In the late 1950s and early 1960s, the Library's collection profile was further expanded as to include publications on European integration, contemporary international relations (including those between the East and the West) and political doctrines. By the 1970s, the Library's holdings had reached 70,000 volumes.

Today, the Library of the Institute for Western Affairs collects publications on contemporary German history, Polish-German relations, the reunification of Germany, transition in Central and Eastern Europe, European and trans-Atlantic integration as well as the international context of Polish problems. The gathered publications concern the political, legal, economic and cultural aspects of these issues. The Institute's Library is one of a handful of libraries in Poland that have succeeded in collecting such an extensive documentation on German and international affairs.

The current holdings of the Library are in excess of 110 thousand items, i.e., books, periodicals and special inventories. The majority of the publications were published after World War II, 60% of them are foreign publications, most originating in German-language countries, some were published in English, French and Slavonic languages. The Library's special collections are especially noteworthy. These include diaries collected in three contests held by the Institute for Western Affairs for various populations in the Western and Northern Territories. The 1957 contest was open to new settlers, the 1966 edition – to the general public, and the 1970 round – to the youth. In total, the collection is comprised of 1077 items. Another interesting collection held at the Library is an archive of photographs of the Western and Northern Territories. The collection includes some 5,500 positives and negatives of photographs taken in the 1940s. These provide invaluable documentation of post-war life in the so-called Recovered Territories.