John Holland Cazale (; August 12, 1935 – March 13, 1978) was an American actor. He appeared in five films over seven years, each of which was nominated for the Academy Award for Best Picture at their respective awards ceremonies. Cazale started as a theater actor in New York City, ranging from regional, to off-Broadway, to Broadway acting alongside Al Pacino, Meryl Streep and Sam Waterston. Cazale soon became one of Hollywood's premier character actors, starting with his role as the doomed, weak-minded Fredo Corleone opposite longtime friend Pacino in Francis Ford Coppola's The Godfather (1972) and The Godfather Part II (1974). He then appeared in Coppola's The Conversation (1974) and Sidney Lumet's Dog Day Afternoon (1975), the latter of which earned him a Golden Globe Award nomination. In 1977, Cazale was diagnosed with lung cancer, but chose to complete his role in The Deer Hunter (1978). He died shortly after, in New York City on March 13, 1978.

Theatrical producer Joseph Papp called Cazale "an amazing intellect, an extraordinary person and a fine, dedicated artist". David Thomson writes that "It is the lives and works of people like John Cazale that make filmgoing worthwhile." A documentary tribute to Cazale, I Knew It Was You, was screened at the 2009 Sundance Film Festival featuring interviews with Pacino, Streep, Robert De Niro, Gene Hackman, Richard Dreyfuss, Francis Ford Coppola, Sidney Lumet and Steve Buscemi.