The game plays as a condensed roguelike with sessions taking only about 10 minutes to play. Players choose a race and class for a character before sending them into a randomly generated dungeon. After completing dungeons, players are rewarded with the ability to unlock new character classes, starting weapons, and bonus dungeons. Players can worship different deities at altars, who then bestow upon the worshipers a set of rules which benefit the player if they are followed or harm them if they are not.
Video game modders can create tilesets for the game which changes the appearance of the dungeon. Derek Yu, the creator of the video game Spelunky, created one such tileset which the developers of Desktop Dungeons decided to use as the default appearance for the game.