Birthname: Joseph Francis Mazzello III
Date of birth: September 21, 1983
Profession: Actor
Nickname: Joe
Hometown: Rhinebeck, New York
Nationality: American
Astral sign: Virgo
Height: 1.75m

Joseph Francis Mazzello III  is an American actor who is best known for his roles as Tim Murphy in Jurassic Park, Eugene Sledge in the HBO miniseries The Pacific, and Dustin Moskovitz in The Social Network.
Mazzello was born in Rhinebeck, New York, and raised in Hyde Park, New York, the son of Virginia (née Strong) and Joseph Mazzello, Jr., who owned a performing arts school. He has one older sister, Mary Mazzello, and a younger brother, John Mazzello, who have both appeared in films. Mazzello went to Catholic school Our Lady of Lourdes. He is an alumnus of the University of Southern California.