Liam O'Brien (gebore 28 Mei 1976) is 'n Amerikaanse akteur en skrywer. Hy is bekend vir sy rolle in die rolprente Final Fantasy VII: Advent Children (2005) en Curse of the Golden Flower (2006), en in die televisiereeks Critical Role (2015).
- 2004: Naruto the Movie: Ninja Clash in the Land of Snow
- 2005: Final Fantasy VII: Advent Children
- 2005: Naruto the Movie 2: Legend of the Stone of Gelel
- 2006: Curse of the Golden Flower
- 2015: The Phoenix Incident
- 2000: Descendants of Darkness
- 2001: Hare+Guu
- 2003: Stellvia
- 2003: Gad Guard
- 2004: Duel Masters
- 2004: Monster
- 2004: The Count of Monte Cristo
- 2004: Girls Bravo
- 2004: Melody of Oblivion
- 2004: Destiny of the Shrine Maiden
- 2004: DearS
- 2005: MÄR: Märchen Awakens Romance
- 2005: Kamichu!
- 2005: Gun x Sword
- 2005: Eyeshield 21
- 2006: Fate/stay night
- 2006: Ergo Proxy
- 2006: Busô renkin
- 2008: Wolverine and the X-Men
- 2008: Blade of the Immortal
- 2010: NFL Rush Zone
- 2013: Nura: Rise of the Yokai Clan: Demon Capital
- 2014: Sengoku Basara: End of Judgement
- 2015: Critical Role
- 2015: CelebriD&D
- 2016: Talks Machina
- 2017: Sagas of Sundry
- 2010: Planet Hulk
- 2012: The Massive
- 2016: Hulk: Where Monsters Dwell
- 2016: Behind the Scenes: The Phoenix Incident