Old Library or Old Library Building may refer to:
Ireland The Old Library building, which forms part of the Library of Trinity College Dublin
United Kingdom Old Library, Bristol, a historic library building dating from 1740 Old Library, Cardiff, previously the main public library for Cardiff, 1882–1988 The Old Library, Liverpool, a former Andrew Carnegie library Old Library Building, one of the Newcastle University buildings at Newcastle University, Newcastle upon Tyne Old Library, Wrexham, Wrexham's former library from 1907
United States Old Library Building (Tucson, Arizona), listed on the NRHP in Pima County, Arizona Old Library Building (Maysville, Kentucky), listed on the NRHP in Kentucky Old Library (Bryn Mawr College), formerly known as the M. Carey Thomas Library Old Library, West Chester, Pennsylvania, dating from 1902 Old Library Building (Chattanooga, Tennessee), listed on the NRHP in Tennessee The Old Library, an alternative name for Battle Hall at the University of Texas at Austin