The player controls a spaceship that can move left, right, up and down around the lower third of the screen. The ship can fire a single shot (called a "quark laser" in this game), which travels vertically up the screen. Unlike similar games, where the player cannot fire again until the existing shot has disappeared, the player can choose to fire another shot at any time, if the previous shot is still on screen, it disappears.

Gorf consists of five distinct "missions", each with its own patterns of enemies. The central goal of each mission is to destroy all enemies in that wave, which takes the player to the next mission. Successfully completing all five missions will increase the player's rank and loop back to the first mission, where play continues on a higher difficulty level. The game continues until the player loses all their lives. The player can advance through the ranks of Space Cadet, Space Captain, Space Colonel, Space General, Space Warrior, and Space Avenger, with a higher difficulty level at each rank. Along the way, a robotic voice heckles and threatens the player, often calling the player by their current rank (for example, "Some galactic defender you are, Space Cadet!"). Some versions also display the player's current rank via a series of lit panels in the cabinet.