Resident Evil Zero is a survival horror video game developed and published by Capcom. It is the fifth major installment in the Resident Evil series and was originally released for the GameCube in 2002. It is a prequel to Resident Evil (1996) and its remake (2002), covering the ordeals experienced in the Arklay Mountains by special police force unit, the S.T.A.R.S. Bravo Team. The story follows officer Rebecca Chambers and convicted criminal Billy Coen as they explore an abandoned training facility for employees of the pharmaceutical company Umbrella. The gameplay is similar to other Resident Evil games, but includes a unique "partner zapping" system. The player controls both Rebecca and Billy, switching control between them to solve puzzles and use their unique abilities.

Resident Evil Zero received generally positive reviews. Critics praised the graphics and audio for building a haunting atmosphere. Opinions on the new partner and item systems were mixed. Some found the changes were an improvement and added new layers of strategy; others believed the changes were cumbersome or non-innovative. The controls were panned as outdated and Capcom was criticized for not evolving the series' tank controls. Resident Evil Zero was commercially successful, having sold over 3.5 million copies across all platforms.