Oliver Platt (born January 12, 1960) is a Canadian-born American actor.

He is known for his roles in many films such as Married to the Mob, Working Girl (both 1988), Flatliners (1990), Beethoven (1992), Indecent Proposal, The Three Musketeers (both 1993), Executive Decision, A Time to Kill (both 1996), Dangerous Beauty, Bulworth, The Impostors, Dr. Dolittle (all 1998), Ready to Rumble, Gun Shy (both 2000), Don't Say a Word (2001), Zig Zag (2002), Pieces of April (2003), The Ice Harvest (2005), Martian Child (2007), Frost/Nixon (2008), Year One (2009), Please Give, Love & Other Drugs, Letters to Juliet (all 2010), and X-Men: First Class, The Oranges (both 2011), Legends of Oz: Dorothy's Return (2013), and Frank and Cindy and One More Time (both 2015). Platt has been nominated for a Golden Globe Award, a Tony Award, two Screen Actors Guild Awards, and four Primetime Emmy Awards.