Church is a human surname that can be used to refer to the following:
- Doctor Leonard Church - Former Director of Project Freelancer and basis for the Alpha A.I. program. Husband of Allison and father of Carolina. Deceased.
- Leonard L. Church / Alpha - Former de facto leader of the Blood Gulch Blue team and the A.I. program based on the former Director of Project Freelancer. Destroyed.
- Epsilon - The A.I. fragment containing the Alpha's memories. Often referred to as "Church" by his teammates due to being nearly identical to Alpha. Destroyed.
- Allison Church - Former UNSC marine, fell in combat in the Great War. Wife of Leonard and mother of Carolina. Deceased.
- Freelancer Agent Texas / Tex / Allison / Beta - The A.I. by-product formed from the Director's memories of his wife. Former Project Freelancer agent. Destroyed.
- Freelancer Agent Carolina, last name Church - Former Project Freelancer agent allied with the Reds and Blues. Daughter of Leonard and Allison.
- Yellow Church - Michael J. Caboose's twisted mental image of Kaikaina Grif, whom he believed to be Alpha-Church's twin brother.
- Genkins - a member of the Cosmic Powers allied with Chrovos who began posing as Church after the paradox.