The Mozilla Application Suite (originally known as Mozilla, marketed as the Mozilla Suite) was a cross-platform integrated Internet suite. Its development was initiated by Netscape Communications Corporation, before their acquisition by AOL. It was based on the source code of Netscape Communicator. The development was spearheaded by the Mozilla Organization from 1998 to 2003, and by the Mozilla Foundation from 2003 to 2006. It has been superseded by SeaMonkey Internet suite (SeaMonkey was the original code name for the project), a community-driven Internet suite that is based on the same source code and continued to be developed with newer Mozilla codebase.

The Mozilla Suite was composed of several main programs: Navigator (a Web browser), Communicator (Mozilla Mail & Newsgroups), a Web page developer (Mozilla Composer), an IRC client (ChatZilla) and an electronic address book. Also included were tools to synchronise the application with Palm Pilot devices, and several extensions for advanced Web development including the DOM Inspector and Venkman (a JavaScript debugger).

Versions 6 and 7 of the Netscape suite were based on the Mozilla Suite. The last official version is 1.7.13, as Mozilla Foundation is now focusing on the development of Firefox and Thunderbird. The Mozilla Suite is available under the terms of the Mozilla project's tri-license, as free and open source software.