The library was born almost in parallel with the modern Archive, at the beginning of the 19th century, and was organized in a systematic way, as a public service, around 1930.
Its content covers large areas of the Archive itself, the archival (methodology and historiography), and history, focusing mostly on the institutional, geographical and chronological scope of the Crown of Aragon (Medieval and Modern European History, History of Spain, etc.)
Currently boasts more than 26,500 copies of monographs, periodicals in course, reaching 168 titles, as well as an interesting background of old magazines.
General and reference works are installed in the Reading Room, are of direct access for researchers, and occupy 115 m/l. The rest of the fund, deposited in one of the chambers, reaches the 1,065 m., and is served on request in the Reading Room.
Information instruments consist of a manual cedulario (cards book) of authors and a manual file of subjects; the works entered from 1996 are available in the automated catalogue of REBAE (Library Network of the State Archives).
Aside, it has a background coming from the institutions that have given rise to the current Archive, composed of printed books from the 16th to the 18th centuries, as well as a manual catalogue.