The library is as old as the museum itself and its foundation is linked to the name of András Jósa. In fact it was triggered by the need of scientific sources in order to process the archaeological finds. András Jósa sought to establish professional links with all the museums and associations in Hungary. As a result, the greatest part of the library comprised different museum and society publications, museum yearbooks, reports and guidebooks. Obviously, the collection contained the whole series of the Archaeological Bulletin and quite a few volumes of Ethnographia.
In the history of the museum the year 1892 marked the renewal of the association. Jósa boasts that the collection was already „displayed on a constant and an elegant place in the house of the County Hall”. Béla Gencsy, the chairman of the ruling party, bought all the volumes from 1868 to 1886 of the Archaeological Bulletin – the leading journal of archaeology in Hungary. The series is complete in the library up to the present day, but since the year 1887 the library can acquire the copies only through purchase.
These are sometimes added to the collection either through purchase or as a membership fee. Purchasing from the poor budget of the museum has been a serious problem from the outset, which hindered scientific research in many respects. (Unfortunately this is still the case today…)

Jósa, as an ardent local patriot, was keen on procuring the books published on local history. A part of these publications was donated by the authors themselves to the museum library. He also sought to acquire the basic works on archaeology.

At the time of András Jósa’s death, a library consisting of approximately 450 volumes could be reconstructed. This estimate is based on the inventory started in 1912 by Lajos Kiss, the guard of the museum, later the museum director.

Samples of books from the museum library in Jósa’s time
- The First Yearbook of The Museum Society from Upper Hungary 1872./Edited by Gy.Húgó Károly- Kassa: Werfer Károly Printing House of the Royal Academy, 1874.
- Report on the Condition of the Székely National Museum in the 1903: the Report of the Board of Directors to the General Inspectorate of Museums and Libraries. - Sepsiszetgyörgy: Jókay Printing House, 1904.