Fritz William Weaver (January 19, 1926 − November 26, 2016) was an American actor. He appeared in over 170 theatre, television, and film productions in a career spanning nearly 60 years.

Weaver won the 1970 Tony Award for Best Actor in a Play and the Drama Desk Award for Outstanding Performance for his performance as Jerome Malley in the original Broadway production of Child's Play, and was nominated for Tony Award for Best Featured Actor in a Play for The Chalk Garden (1958). He was also well-known as a Shakespearean, and for his portrayal of Sherlock Holmes in the musical Baker Street.

On screen, he made his film debut in Sidney Lumet's Fail Safe (1964), and appeared in Marathon Man (1976), Black Sunday (1977), Demon Seed (also 1977), Creepshow (1982), and The Thomas Crown Affair (1999).

Weaver portrayed Dr. Josef Weiss in the 1978 television miniseries Holocaust, for which he was nominated for a Primetime Emmy Award for Outstanding Lead Actor in a Limited Series or Movie. He was also a fixture as a featured and guest actor on science fiction and fantasy shows, including The Twilight Zone, 'Way Out, Night Gallery, The Martian Chronicles, Star Trek: Deep Space Nine, and The X-Files. He also narrated many educational television programs.