Joseph Leo Mankiewicz (February 11, 1909–February 5, 1993) was a Polish-American Hollywood screenwriter, director and producer.

Born in Wilkes-Barre, Pennsylvania, Mankiewicz moved with his family to New York City where he graduated from Stuyvesant High School. In 1928, he obtained a bachelor's degree from Columbia University. For a time he worked in Berlin, Germany as a foreign correspondent for the Chicago Tribune newspaper before being lured into the motion picture business.

During his long career in Hollywood, Mankiewicz wrote forty-eight screenplays, including All About Eve, for which he won an Academy Award. He also produced more than twenty films including The Philadelphia Story which won the Academy Award for Best Picture in 1941. However, he is best known for the films he directed, twice winning the Academy Award for Directing.

He was the younger brother of Herman J. Mankiewicz.

On his passing in 1993, Joseph Mankiewicz was interred in Saint Matthew's Episcopal Churchyard cemetery, Bedford, New York.

Award wins (partial):

• 1949 - Academy Award for Directing for A Letter to Three Wives
• 1949 - Academy Award for Writing Adapted Screenplay for A Letter to Three Wives
• 1949 - Directors Guild of America Awards for A Letter to Three Wives
• 1950 - Academy Award for Directing for All About Eve
• 1950 - Academy Award for Writing Adapted Screenplay for All About Eve
• 1951 - Cannes Film Festival - Jury Special Prize

Award nominations (partial):

• 1931 - Academy Award for Writing Adapted Screenplay for Skippy
• 1942 - Academy Award for Writing Adapted Screenplay for A Letter to Three Wives
• 1950 - Academy Award for Writing Original Screenplay for No Way Out
• 1952 - Academy Award for Directing for 5 Fingers
• 1954 - Academy Award for Writing Original Screenplay for The Barefoot Contessa
• 1972 - Academy Award for Directing for Sleuth

Partial filmography (directing):

• Skippy (1931)
• The Philadelphia Story (1940)
• Dragonwyck (1946)
• Backfire (1946)
• Somewhere in the Night (1946)
• The Late George Apley (1947)
• The Ghost and Mrs. Muir (1947)
• Escape (1948)
• House of Strangers (1949)
• A Letter to Three Wives (1949)
• All About Eve (1950)
• No Way Out (1950)
• People Will Talk (1951)
• Julius Caesar (1953)
• The Barefoot Contessa (1954)
• Guys and Dolls (1955)
• The Quiet American (1958)
• Suddenly, Last Summer (1959)
• Cleopatra (1963)
• Carol for Another Christmas (1963)
• The Honey Pot (1967)
• There Was a Crooked Man... (1970)
• King: a Filmed Record...Montgomery To Memphis (1970)
• Sleuth (1972)