Daniel Michael DeVito Jr. (born November 17, 1944) is an American actor, comedian, director, and producer. He first gained prominence as the irascible dispatcher Louie De Palma on Taxi, for which he won a Golden Globe and an Emmy. He plays Frank Reynolds on the long-running sitcom It's Always Sunny in Philadelphia (2006 - present).

In film, DeVito is known for his roles in One Flew Over the Cuckoo's Nest (1975), Terms of Endearment (1983), Head Office (1985), Ruthless People (1986), Twins (1988), Batman Returns (1992), Jack the Bear (1993), Junior (1994), L.A. Confidential (1997), The Big Kahuna (1999), Big Fish (2003), Deck the Halls (2006), When in Rome (2010), Wiener-Dog (2016) and Jumanji: The Next Level (2019). DeVito has voiced characters in numerous animated films including Space Jam (1996), Hercules (1997), The Lorax (2012), Smallfoot (2018), and Migration (2023). He both directed and starred in several films such as Throw Momma from the Train (1987), The War of the Roses (1989), Matilda (1996), and Death to Smoochy (2002). He has served as a producer on notable films such as Reality Bites (1994), Pulp Fiction (1994), Gattaca (1997), Erin Brockovich (2000), and Garden State (2004).

DeVito married actress Rhea Perlman in 1982; they have three children. The couple separated in 2012.