Deep Rock Galactic is a cooperative first-person shooter. Gameplay primarily centers around missions that take place in fully destructible, procedurally generated cave systems; each has varying terrain generation, objectives, hazards, and enemies depending on the selected biome and mission type.

The game features various progression systems, such as new weapons, equipment upgrades, and cosmetics, that can be purchased using credits and crafting minerals obtained from missions. By completing challenges, players can also acquire perks; these give dwarves additional abilities, such as increased running speed.

Players can play missions solo or with up to three other players. Before starting each mission, players choose one of four playable classes: Scout, Engineer, Gunner, and Driller. Each class has a unique loadout of weapons and tools, giving them varied capabilities in combat and navigation. By working together to take advantage of how these different capabilities interact, teams can more efficiently navigate a cave, complete objectives, and fight enemies.