The National Library of Uganda was established by the National Library Act, 2003. This Act repealed the Public Libraries Act, 1964 which had established the Public Libraries Board. The Board had been charged with the responsibility of establishing, equipping, managing and maintaining libraries in Uganda. Following the enactment of the Local Governments Act, 1997, this responsibility was decentralized to the local governments. The Public Libraries Board and later the National Library of Uganda retained the responsibility of laying down national policies in regard to these libraries, giving advice, issuing standards, norms, guidelines and work manuals, providing technical and professional advisory services and coordinating and carrying out advocacy for these libraries at local and international levels.

With the enactment of the National Library Act, 2003, the NLU became the National Bibliographic Control Agency responsible for ensuring legal deposit of materials by publishers, publishing the National Bibliography of Uganda, allocating the International Standard Book Numbers (ISBN) and International Standard Serial Numbers (ISSN) and establishing and managing a National Collection of Uganda.