- National and University Library in Zagreb (Croatian: Nacionalna i sveučilišna knjižnica u Zagrebu, NSK; formerly Nacionalna i sveučilišna biblioteka u Zagrebu, NSB) is the national library of Croatia and central library of the University of Zagreb.
The national library was founded in 1607. Its primary mission is the development of the national literary corpus. It has around 2.5 million books.
NSK is currently located in a standalone building in the center of Trnje on the Hrvatske bratske zajednice street, where it moved in 1995. The building is the work of renowned Croatian architects Velimir Neidhardt, Marijan Hržić, Zvonimir Krznarić and Davor Mance, and its construction took six years (1978-1984).