Six Days in Fallujah is a tactical first-person shooter video game developed by Highwire Games and published by Victura. Set in the Second Battle of Fallujah of the Iraq War over the span of six days in November 2004, the game follows the United States Marine Corps' 3rd Battalion, 1st Marines (3/1) as they fight the Iraqi insurgency in the city of Fallujah, Iraq. Its campaign follows two perspectives: a squad of Marines from 3/1 deployed to battle the insurgents, and an Iraqi family attempting to escape the city in the midst of the battle.

Originally developed by Atomic Games, Six Days was announced in 2009, with a release slated for 2010, published by Konami; however, controversy surrounding the game's appropriateness and handling of its contentious and then-very-recent subject matter led to Konami departing the project, and Atomic Games' bankruptcy in 2011 left the game on hold indefinitely. Around 2016, Victura and Highwire began developing a revived version of the game, which was announced in February 2021. After several delays, Six Days in Fallujah was released in early access on Microsoft Windows on June 22, 2023, and is planned to come to consoles such as the PlayStation 4, PlayStation 5, Xbox One, and Xbox Series X/S in 2026.