NLC Ancient Books Library, Ancient books repository in Shichahai Subdistrict, Beijing, China.

The National Library of China Ancient Books Library occupies the 1931 former National Beiping Library on Wenjin Street, west of Beihai Park. Its main building, Wenjin Tower, is a Chinese palace-style structure modelled on the Hall of Supreme Harmony, with a 76-mu site and 30,000 square metres of floor space. The central reading room once seated over 200 people.

The library traces its origin to the Jingshi Library, approved by Emperor Xuantong on 9 September 1909 and opened to readers in August 1912 in the Guanghua Temple. In 1929 construction began on a new building beside the western shore of Beihai, funded by the China Foundation for the Promotion of Education and Culture from returned US Boxer indemnity funds. It opened on 25 June 1931 as the National Peiping Library, and the Wenjin Pavilion copy of the Siku Quanshu was moved in. The building became a branch in 1987 and was renamed the Ancient Books Library in 2005.

The street outside was named Wenjin Jie in 1931 after the Wenjin Ge edition of the Siku Quanshu, which was moved into the new building that year. The library's name changes trace the institution: Jingshi Library, Beiping Library, then the National Library's ancient books branch in 2005.

The library is at 7 Wenjin Street in the Shichahai Subdistrict of Xicheng District, on the west bank of Beihai. It closed on 2 April 2024 for restoration of the former Beiping Library building, so check reopening before travelling; the 1931 reading room originally seated about 200 people.

The library's name comes from the Wenjin Ge edition of the Siku Quanshu, moved here in 1931; the street in front was renamed Wenjin Street that same year to mark it. In the courtyard stand two huabiao columns brought from the Yuanmingyuan; a mix-up during their transfer left each library with one column from inside and one from outside the gate.