Bianca was born into a well-situated family. Her father was a businessman and her mother a housewife. They divorced when Bianca was ten and she stayed with her mother, who had to take care of four children on a small income. When Bianca was studying political science in Paris, she demonstrated against the Somoza regime after the massacre of students perpetrated by Somoza's National Guard. In Paris, she also became acquainted with French literature, among which especially Voltaire, Rousseau and Camus influenced her. She has also been fascinated by Gandhi's non-violent success and the eastern philosophy at large. She travelled extensively in India.

In 1971, she became the first wife of Mick Jagger. Leni Riefenstahl made some well known photos of them as a couple. In this time Bianca became concerned with women's rights. The couple had one daughter, Jade Jagger (born on October 21, 1971), but divorced in 1979. In the 1970s and early 1980s, Bianca Jagger was known as a jet-setter and party-goer, being notoriously associated with New York's nightclub Studio 54. She has had relationships with two US Democratic politicians, Robert Torricelli and Christopher Dodd. Billy Joel's song "Big Shot" is based on a bad date with Bianca.

The end of her marriage coincided with the victory of the Sandinista revolution. In the spring of 1979, Bianca visited Nicaragua with an International Red Cross delegation and was shocked by the brutality and oppression that the Somoza regime carried out there. This persuaded her to commit herself to the issues of justice and human rights.

In the 1980s, she fought to instruct the public about the military interventions, supported by the U.S.A., which were directed against the Sandinista regime in Nicaragua and which brought much suffering of ordinary people. She has also opposed the death penalty and defended the rights of women and of indigenous peoples in Latin America, notably the Yanomami tribe in Brazil against the invasion of gold miners. She fought against the aerial bombardment of Serbia by NATO in 1999 during the Kosovo war, but also has all the time been supporting victims of the ethnic cleansing in Bosnia. Her writings were published in several newspapers (e.g. New York Times, Sunday Express). From the late 1970s she collaborated with many humanitarian organizations:

for Amnesty International, she is a member of the Executive Director's Leadership Council for Human Rights Watch/America, she is a member of the advisory Committee for Coalition For International Justice, she is a member of the advisory committee for Indigenous Development International, she is a special advisor for People for the American Way, she is a board member She is also a member of the Twentieth Century Task Force to Apprehend War Criminals, and of the Washington Office for Latin America.

For her work, Bianca Jagger earned several awards. Especially prominent among these are the 1994 United Nations Earth Day award, the 1997 Green Globe award from the Rain Forest Alliance for her efforts on behalf of saving tropical rain forests and an "Abolitionist of the Year" award from the National Coalition to Abolish the Death Penalty.

Bianca Jagger also gave a reading at the start of the memorial service in London's Westminster Cathedral, which was timed to coincide with the funeral in Brazil of Brazilian Jean Charles de Menezes, who was shot eight times on a tube-train after being mistaken for a suicide bomber in London.

Bianca Jagger also appeared in several movies: Cocksucker Blues (1972), The Rutles: All You Need Is Cash (1978, as Martini), The American Success Company (1979; as Corrine), The Cannonball Run (1981, as sheik's sister), In Our Hands (1984), C.H.U.D. 2 (1989), The Party's Over (2003, a documentary movie on American politics).