Game over is the ending text of many video games. Used first in arcade games, it was later adopted widely and now is commonly associated with video games in general.

The phrase was originally used at the end of games, whether the player has won the game or not. Most games of today use other ending texts such as "The End," or simply an ending cutscene and credits, if the player is successful, with "Game Over" used to signify failure. Some games use Game Over not only to indicate the end of the game, but also to indicate that the game is not currently being played.

The way in which the phrase is used varies between games. Some, in particular older games such as Space Invaders, have the phrase "Game Over" as text simply super-imposed on the game screen, while other games, particular more recent ones, have a separate game over screen. These tend to be more elaborate, and the phrase may be animated, and accompanied by graphics.

Some games make advantage of the Game Over screen to add depth to the game itself, sometimes at the expense of the fourth wall. The Metal Gear series is particularly notorious for this. Metal Gear Solid 2: Sons of Liberty, for example, uses a false Game Over screen to trick the player into believing that he has suddenly lost, when in fact the game is continuing in a small window in the corner. Metal Gear Solid 3: Snake Eater contains a "fake death pill" that creates a fake Game Over screen for the duration of the fake death, as well as a boss that can only be defeated by negotiating out of a Game Over screen after the player's character dies. A flashing Game Over message was also displayed after the end credits of the UK gaming television series Gamesmaster.

The phrase "game over" also has taken on relevance outside of gaming. It is sometimes used to signify an abrupt end, similar to the one a player might meet in a video game. In the 1986 movie Aliens, Bill Paxton's character Hudson uses the phrase to indicate what he thinks is a hopeless situation: "... Game over, man! Game over!" This phrase, shortened to "Game over, man!", was later used as part of the game over screen of the SNES video game Alien 3, based on the film of the same name.

The phrase does not neccesarily appear if the player has died. Often, the player will get a certain number of turns (often describes as 'lives' in games where the player loses when his/her character dies), but when these are used up, the player is in a game over situation. However, it is sometimes possible for play to go on even after this, if the player has "continues" (or "credits"), which are additional sets of lives available, or a previously saved game exists. In arcade games, continues, when they exist, typically only require the insertion of the appropriate amount of money (coins) within a time limit, and are otherwise unlimited. In console games, the player usually has to collect certain amount of items or points to acquire extra continues.