数字图书馆（Digital Library），亦即数字图书馆，是一种馆藏以数码化格式保存可以利用电脑访问的图书馆，而传统图书馆的馆藏则以印刷、微缩胶片或其他媒体等相对格式为馆藏主体。数字化的内容可以被存在本地端或透过电脑网络由远程访问。数字图书馆可说是一种信息检索系统。

DELOS数字图书馆的委员定义了数字图书馆，内容如下：

对于印刷品数字图书馆的第一个用途也许是在1988年报告到全国主动性研究公司。在1994年，数字图书馆由NSF/DARPA/NASA数字图书馆首先大众化。虽然现在还会偶尔使用旧称如电子图书馆（Electronic Library）或虚拟图书馆（Virtual Library），但是现在英文的"Electronic Library"多数是指由政府机构提供的入口系统，例如佛罗里达州电子图书馆（Florida Electronic Library）。

A digital library is a special library with a focused collection of digital objects that can include text, visual material, audio material, video material, stored as electronic media formats (as opposed to print, microform, or other media), along with means for organizing, storing, and retrieving the files and media contained in the library collection. Digital libraries can vary immensely in size and scope, and can be maintained by individuals, organizations, or affiliated with established physical library buildings or institutions, or with academic institutions. The digital content may be stored locally, or accessed remotely via computer networks. An electronic library is a type of information retrieval system.