The historic collection preserved by the Foundation is one of the broadest and most detailed in Europe in the fields of history, political, economic and social sciences. The collection contains more than 1,5 million archive pieces, 250.000 volumes, 17.500 periodical newspapers and 14.000 posters.

The archival collection ranges from individual and family archives (the Feltrinelli Family Funds, Angelo Tasca, Pietro Secchia, Rinaldo Rigola, Felice Cavallotti, Leo Valiani) to the records of corporations, institutions and company funds (Biblioteca Istituto Feltrinelli, Giangiacomo Feltrinelli Editore), from a documentary collection (on the Solidarnosc movement and The Prague Spring, the collection about democratic movements in contemporary China, the archive of the New Italian Left, the Spanish civil war, the European Resistance), to posters and affiches (the Italian, French and German revolts of 1948, the caricatures and manifestos of the Paris Commune, the Italian political posters from the post second world war period, the Alberto Sandretti collection of soviet posters).

The library preserves approximately 4.500 ancient and rare books, many of which are first-edition copies, published between the 16th century and the first half of the 19th century. Among the most valuable volumes it is possible to find the 1518 edition of Utopia by Thomas More, and first or rare editions of Hugo Grotius, William Petty, John Locke and Thomas Hobbes.