The Library was established at the founding of the Warsaw University in 1817, acquiring such collections as those of the Warsaw Lyceum, the private libraries of King Stanisław Poniatowski and Stanisław Kostka Potocki, as well as libraries from suppressed monasteriers.
The University Library is one of the three largest collections of scholarly books in Poland. Not only does it function as the University's main library, but also as a public library. It contains domestic and foreign works from each of the disciplines of the arts and sciences studied and taught at the University, with collections in the humanities and social sciences most thoroughly represented. The Library numbers approximately 2,400,000 volumes, including more than 1,500,000 books, 600,000 volumes of periodicals, early imprints, manuscripts, graphics, musical scores, maps, and microfilms. As a whole the Library regularly serves more than 20,000 readers, with more than 300,000 items accessed and lent annually.