Glenn Howerton (gebore 13 April 1976) is 'n Amerikaanse akteur, skrywer, en vervaardiger. Hy is bekend vir sy rolle in die rolprente Serenity (2005), Crank (2006), en The Strangers (2008), en in die televisiereeks It's Always Sunny in Philadelphia (2005).
- 2005: Serenity
- 2006: Crank
- 2008: The Strangers
- 2010: It's Always Sunny in Philadelphia: Cast & Creators Live at the Paley Center
- 2013: Coffee Town
- 2002: That '80s Show
- 2005: It's Always Sunny in Philadelphia
- 2011: Vietnam in HD
- 2011: Dennis & Dee's Podcast
- 2018: A.P. Bio
- 2003: E.D.N.Y.
- 2004: It's Always Sunny on TV
- 2009: Boldly Going Nowhere
- 2007: It's Always Sunny in Philadelphia: Making of Season 1 & 2
- 2007: Two Weeks: Learning to Live through Dying
- 2008: It's Always Sunny in Philadelphia Season 3: Dancing Guy
- 2008: It's Always Sunny in Philadelphia Season 3: Meet the McPoyles
- 2008: It's Always Sunny in Philadelphia Season 3: Sunny Side Up
- 2008: It's Always Sunny in Philadelphia: Sunny Side Up
- 2009: The Nightman Cometh Live!