Joaquin Rafael Phoenix (/hwɑːˈkiːn/ ^ⓘ whah-KEEN; né Bottom; born October 28, 1974) is an American actor. Widely described as one of the preeminent actors of his generation and known for his roles as dark, unconventional and eccentric characters in independent cinema, he has received various accolades, including an Academy Award, a BAFTA Award, a Screen Actors Guild Award, a Grammy Award, and two Golden Globes.

Phoenix began his career by appearing in television series in the early 1980s with his brother River. His first major film roles were in SpaceCamp (1986) and Parenthood (1989). During this period, he was credited as Leaf Phoenix, a name he gave himself. He took back his birth name in the early 1990s and received critical acclaim for his supporting roles in the comedy-drama To Die For (1995) and the period film Quills (2000). Phoenix received further critical acclaim and a nomination for the Academy Award for Best Supporting Actor for his portrayal of Commodus in the historical drama Gladiator (2000). He had success with the horror films Signs (2002) and The Village (2004), the historical drama Hotel Rwanda (2004), and won a Grammy Award, a Golden Globe Award, and a nomination for the Academy Award for Best Actor for his portrayal of musician Johnny Cash in the biopic Walk the Line (2005).

Following a brief sabbatical, Phoenix starred in the psychological drama The Master (2012), winning the Volpi Cup for Best Actor and earning his third Academy Award nomination. He gained praise for his roles in the romantic drama Her (2013) and the crime satire Inherent Vice (2014), and won the Cannes Film Festival Award for Best Actor for the psychological thriller You Were Never Really Here (2017). For his performance as the titular character of Joker (2019), Phoenix won the Academy Award for Best Actor. He reprised his role in the 2024 sequel. He has since starred in the independent films C'mon C'mon (2021), Beau Is Afraid (2023) and Eddington (2025), and portrayed the title role in the historical drama Napoleon (2023).

Outside acting, Phoenix is an animal rights activist. A vegan, he regularly supports charitable causes and has produced several documentaries on global meat consumption and its impact on the environment.

Phoenix was born at the Hospital Metropolitano San Francisco in the Río Piedras district of San Juan, Puerto Rico, to John Lee Bottom, the founder of a landscape gardening company, and Arlyn "Heart" Bottom (née Dunetz), an executive secretary at NBC and whose connection to an agent provided her children with acting work. Joaquin is the third of five children, following River (1970–1993) and Rain (born 1972), and preceding Liberty (born 1976) and Summer (born 1978), all of whom have been involved in acting. He also has a paternal half-sister, Jodean (born 1964). His father was a Catholic from Fontana, California, and was of English, German and French ancestry. His maternal grandfather, Meyer Dunetz, was Russian Jewish and his maternal grandmother, Margit Lefkowitz, was Hungarian Jewish; they were both Ashkenazi Jews who resided in New York City. Phoenix's parents met when his mother was hitchhiking in California; they married less than a year after meeting.

Soon after their second child was born, they joined the religious cult Children of God and travelled throughout the Caribbean and South America as missionaries, where the next two children were born. They eventually became disillusioned with the group and left in 1977, being opposed to the cult's increasingly questionable rules, particularly the practice of flirty fishing. The fifth child was born in Florida where the family settled; around this time they legally adopted the surname Phoenix, inspired by the mythical bird that rises from its own ashes, symbolizing a new beginning. When Joaquin was three, he and his older siblings witnessed fish being stunned as "they were throwing them against the side of the boat", prompting the whole family to convert to a vegan lifestyle.

In 1979, when Phoenix's father had to stop working because of an old spinal injury, the family moved to Los Angeles where the mother met a high-profile child agent named Iris Burton, who got the children into commercials and bit parts on TV. Phoenix made his acting debut alongside his brother in the television series Seven Brides for Seven Brothers in the 1982 episode "Christmas Song". He has said of his first acting experience:

Instantaneous joy. The most enjoyable thing. For some kids, it's the first time they crack a ball or score a goal. For me, it was this. I was eight years old, and I remember the first scene on the TV set so vividly. And I knew that I loved it – the physical sensation; how powerful it was. That's the feeling I've been chasing ever since.