Biblioteca Pública do Estado do Rio de Janeiro, Public library in Rio de Janeiro, Brazil.

The Biblioteca Pública do Estado do Rio de Janeiro is a public library in central Rio de Janeiro, Brazil, spread across several floors with reading rooms, reference collections, and research areas. Each floor is dedicated to a different type of material, making it easier for visitors to find what they are looking for.

Created on 15 March 1873 on the proposal of Antônio Barroso Pereira, president of the city council, the library was inaugurated by Emperor Dom Pedro II on 2 December 1874, his 49th birthday, as the Biblioteca Municipal do Rio de Janeiro. It moved to Avenida Presidente Vargas 1261 in 1943 and took the name Biblioteca Estadual Celso Kelly in 1980. A fire on 20 January 1984 destroyed part of the building and collection; the rebuilt library opened on 12 March 1987 under Darcy Ribeiro's cultural programme, and after works from 2008 it reopened on 29 March 2014 as Biblioteca Parque Estadual.

The name changes follow Rio's political status: Biblioteca Municipal do Rio de Janeiro (1874), Biblioteca Municipal do Distrito Federal (1891), Biblioteca Estadual da Guanabara (1960), Biblioteca Estadual do Rio de Janeiro (1975), Biblioteca Estadual Celso Kelly (1980). The 2014 reopening as Biblioteca Parque Estadual came with an exhibition on Vinicius de Moraes; the collection holds about 200,000 titles.

Checking the digital catalog before your visit helps you locate specific materials and saves time once you are inside. For deeper research, specialized librarians are available on each floor to guide you through the different sections.

During the 2008–2014 renovation, workers uncovered an archaeological site on land that had belonged to the neighbouring Igreja de São Gonçalo e Garcia e São Jorge. The library reopened on 29 March 2014 with an exhibition on Vinicius de Moraes. The building stands about 500 metres from the Sambadrome.