Cameron Michelle Diaz (born August 30, 1972) is an American actress. Prolific in comedy and drama, her films have grossed over $3 billion at the U.S. box office. Her output of romantic comedies in the late 1990s and early 2000s established her as a prominent sex symbol and one of Hollywood's most bankable stars, and in 2013, she was named the highest-paid actress over 40. Diaz has received various accolades, including nominations for a British Academy Film Award and four Golden Globe Awards.

Born in San Diego, California, Diaz was raised in Long Beach. While still in high school, she signed a modelling contract with Elite Model Management. She made her film debut at age 21 opposite Jim Carrey in the comedy The Mask (1994). Following a supporting role in the romantic comedy My Best Friend's Wedding (1997), she starred as the titular character in the Farrelly brothers' comedy There's Something About Mary(1998), which brought her increased fame and her first Golden Globe nomination. Her following two projects—the sports drama Any Given Sunday and Spike Jonze's fantasy film Being John Malkovich (both 1999)—earned Diaz recognition as a dramatic actress.  Diaz received praise for her supporting roles in Cameron Crowe's Vanilla Sky (2001) and Martin Scorsese's Gangs of New York (2002) and had tremendous commercial success in the action comedy Charlie's Angels (2000) and its 2003 sequel, as well as for voicing Princess Fiona in the Shrek franchise (2001–present). Her subsequent films include the comedies In Her Shoes (2005), The Holiday (2006), What Happens in Vegas (2008), Knight and Day (2010), The Green Hornet (2011), and Bad Teacher (2011). After starring in three successful comedies in 2014—The Other Woman, Sex Tape, and Annie—Diaz retired from acting to focus on her family but returned to the profession with the action comedy Back in Action (2025). Diaz has also written two health books: The Body Book (2013), a New York Times bestseller, and The Longevity Book (2016). Her personal life has drawn media attention throughout her career, mainly regarding her relationships and fashion choices. In 2015, Diaz married Good Charlotte guitarist Benji Madden; they have two children via surrogate.