Robert Offer said she filed for "dissolution of marriage" on Monday, adding the "decision was made for the health of the family".
"She will not be commenting, and asks that the family be given its privacy at this time," Offer added in a statement.
The couple have been together since 2004 but only married in August 2014.
Ms Jolie's longtime manager Geyser Kosinski told E! Online: "Angelina will always do what's in the best interest of taking care of her family."
It was Pitt's second marriage, having previously wed Friends star Jennifer Aniston, and Jolie's third after Billy Bob Thornton and Jonny Lee Miller.
According to US entertainment website TMZ, the divorce papers listed the date of separation as 15 September.
It is understood Jolie is seeking physical custody of the couple's six children and is asking the judge to give Pitt visitation rights.
The couple have six children together - Maddox, Pax, Zahara, who are adopted, and biological children Shiloh and twins Knox and Vivienne.
Pitt, 52, and Jolie, 41, married privately in the French hamlet of Correns in Provence in 2014.
Their children served as ring bearers at the wedding and helped illustrate Jolie's white dress with their drawings.
Jolie is well known for her charity work - she served as a Goodwill Ambassador for the United Nations Refugee Agency for 11 years before becoming a Special Envoy in April 2012.
In 2013, she announced she had undergone a double mastectomy to reduce her chances of getting breast cancer.
She wrote about the experience for the New York Times, saying that she made the choice after her doctor said she was highly at risk of developing breast cancer
"Once I knew that this was my reality, I decided to be proactive and to minimise the risk as much I could," she said.
Two years later, she had her ovaries and fallopian tubes removed as a preventative measure against cancer.
Last year, ahead of the release of By The Sea, the romantic drama the couple both star in, Jolie told The Telegraph: "Brad and I have our issues.
"We have fights and problems like any other couple. We have days when we drive each other absolutely mad and want space, but the problems in the movie aren't our specific problems."
Jolie will reportedly be represented by lawyer Laura Wasser, whose previous clients include Johnny Depp, Kim Kardashian, Stevie Wonder and Britney Spears.
Jolie and Pitt - nicknamed "Brangelina" by fans - are one of the best-known couples in Hollywood.
They got together after meeting on the set of the film Mr & Mrs Smith, which was released in 2005.
Jolie, who is the daughter of actor Jon Voight and actress Marcheline Bertrand, rose to fame with roles in films such as The Bone Collector and Girl, Interrupted, for which she won a best supporting actress Oscar in 1999.
She starred as Lara Croft in the Tomb Raider film series and went on to appear in Changeling, Salt, A Mighty Heart, Wanted and Maleficent.
She also directed World War Two prisoner of war film Unbroken.
Pitt's early acting roles include appearing alongside Susan Sarandon and Geena Davis in Thelma and Louise.
He went on to appear in films including Fight Club, Ocean's Eleven, World War Z, Snatch and The Curious Case of Benjamin Button.
His producing work includes 12 Years A Slave, which won a best picture Oscar in 2014 and The Big Short, in which he also acted.
Pitt and Jolie most recently worked together on 2015 film By The Sea - a relationship drama written, directed and produced by Jolie.
It focused on a couple trying to repair their marriage while staying at a French hotel.