A gaming crossover (short: crossover) occurs when otherwise separated fictional characters, stories, settings, universes, or media in a video game meet and interact with each other. These may exist as a gimmick if two separate games in question are developed by the same company. Otherwise, they may exist as a gag from a rival company.

The following is a list of games in which crossovers appear in either the form of a cameo of any kind, a guest character, or the theme of "crossover" in general in a video game itself:

First and Second-party crossovers

This includes crossovers and cameos of characters from games owned by one company and close affiliates.

Major Crossover

A character from another First or Second party franchise appears as a playable character or boss in the game.

Third-party crossovers

This includes games which have crossovers from two or more separate companies.