Libertini was born in Cambridge, Massachusetts, and graduated from Emerson College in Boston.^[2] During his early years, Libertini worked in New York City and in Chicago. He moved to Los Angeles to pursue an acting career during the 1960s.^[2]

He was an original cast member of The Mad Show, a 1966 Off-Broadway musical-comedy produced by Mad magazine. His first film appearances were in The Night They Raided Minsky's (1968), Don't Drink the Water (1969) and Catch-22 (1970).^[3]

Two of his more memorable film roles came in the comedies Fletch (1985), in which he played Chevy Chase's character's doubting editor, a role he repeated in the 1989 sequel Fletch Lives, and The In-Laws (1979), in which he played General Garcia, an insane Latin American dictator whose closest advisor was a cartoon face drawn on his own hand a la Señor Wences. He portrayed Nosh, an electronics expert who is a childhood best friend of Burt Reynolds's character, in Sharky's Machine (1981).

He also played a traveling vaudevillian in Terrence Malick's Days of Heaven (1978), the greengrocer George W. Geezil in Robert Altman's Popeye (1980), a Hispanic priest in Best Friends (1982), the servant Giuseppe in Unfaithfully Yours (1984), spiritual advisor Prahka Lasa ("Back in Bowl!") in All of Me (1984), the bandit Dijon in Disney's animated feature film DuckTales the Movie: Treasure of the Lost Lamp (1990), and a rabbi in Lethal Weapon 4 (1998).

On television, Libertini was a series regular in the first season of Soap as the Godfather. He appeared as three different characters in episodes of Barney Miller. He also appeared in Evaluation (1978) and Middle Age (1979). He guest starred in the Star Trek: Deep Space Nine episode "Accession" as a Bajoran named Akorem Laan, and in the Sonny with a Chance episode "Dakota's Revenge" as Izzy, an insane mechanic. He also voiced Wally Llama on Animaniacs, and starred in three short-lived sitcoms: Family Man (1988), in which he played a middle-aged comedy writer who married a much younger woman and became a father late in life; The Fanelli Boys (1990–1991), in which he played an Italian priest; and Pacific Station (1991–1992), in which he played a police detective.

Libertini appeared on the TV show Supernatural. His final film role was that of a fisherman in the 2011 film Dolphin Tale. From October 2011 through January 2012, Libertini appeared on Broadway as a rabbi in "Honeymoon Motel", the Woody Allen-penned segment of Relatively Speaking.^[2]

Libertini married actress Melinda Dillon on September 30, 1963;^[4] he had one child with her, Richard.^[5] They divorced in 1978.^[6]

Libertini died at the age of 82 in Venice, California, on January 7, 2016, from cancer. He had been diagnosed two years prior.^[1][7]

• Richard Libertini at IMDb