The National Library of Poland (Polish: Biblioteka Narodowa) is the central Polish library, subject directly to the Ministry of Culture and National Heritage of the Republic of Poland. It was founded in 1928.
The library collects books, journals, electronic and audiovisual publications published in the territory of Poland, as well as Polonica published abroad. It is the most important humanities research library, the main archive of Polish writing and the state centre of bibliographic information about books. It also plays a significant role as a research facility and is an important methodological center for other Polish libraries.
The National Library receives a copy of every book published in Poland as legal deposit. The Jagiellonian Library is the only other library in Poland to have a national library status.
More information on the Wikipedia page 
The website (in Polish) is .