RSS Guard is a free and open-source news aggregator for web feeds and podcasts. It is written in C++ and uses Qt, which allows it to fit with the look and feel of different operating systems while remaining cross-platform. It includes a file downloader, advanced network proxy configuration, and supports external media viewing tools.

RSS Guard is released under the GPL-3.0-only license and is available for Windows, macOS, OS/2 and various Linux distributions.

The feed formats supported by RSS Guard are RSS/RDF, Atom, and JSON Feed. RSS Guard also supports Sitemaps.

RSS Guard can synchronize data with online feed services Tiny Tiny RSS, Nextcloud News, Feedly, Inoreader, feed readers which use Google Reader's API such as FreshRSS, The Old Reader, and Bazqux. The application may also act as a simple e-mail client for Gmail.

RSS Guard is able to automatically detect all types of supported content given URL input.

RSS Guard can mark articles as read, unread, and important. Both article and feed lists can be filtered using regular expressions.

Time intervals for fetching feeds are configurable, and, through feed settings, they can be adjusted for each feed separately.

RSS Guard is bundled with JavaScript engine which is used to write article filters - small scripts which define how the application should react when new article is downloaded.