George Bizos (Greek: Γιώργος Μπίζος; 14 November 1927 – 9 September 2020) was a Greek-South African human rights lawyer who campaigned against apartheid in South Africa. He represented Nelson Mandela during the Rivonia Trial. He instructed Mandela to add the qualification "if needs be" to his trial address, which is credited with sparing him from a sentence of death. Bizos also represented the families of anti-apartheid activists killed by the government, throughout the hearings of the Truth and Reconciliation Commission. He also represented victims of the Marikana massacre.

Bizos was the son of Antonios "Antoni" Bizos, the mayor of the small village of Vasilitsi, south of Koroni and Kalamata on the Messenia peninsula of the Peloponnese, Greece. He was born on 14 November 1927, although this was erroneously recorded on his South African identity documents as 1928, owing to his father's declaration to the authorities upon arrival in Egypt.

In May 1941 at the age of thirteen, Bizos and his father helped seven New Zealand Army soldiers (Don Gladding, Mick Karup, Peter Martin, John Lewis and three others) who were hiding in the hills to escape the German-occupied Greek mainland for Crete. The nine set out to sea at night, with only a cheap compass and a map torn from an atlas, intending to escape to Crete. On the second day at sea, rough winds took the sail out of control and tore through its canvas. The men had to take turns to row throughout the night until they managed to repair the sail. On the third day, they spotted a ship in the distance. They managed to attract the attention of the crew of what turned out to be the British destroyer, HMS Kimberley, on its way to the Battle of Crete. After the battle, the Kimberley dropped him and his father off at Alexandria, Egypt.

As a refugee, Bizos was sent to the Union of South Africa and landed in Durban. From there he went by train to Johannesburg, disembarking at the Braamfontein railway station. At the time, the Ossewabrandwag, an Afrikaner group with Nazi sympathies, were demonstrating against the arrival of refugees. The Ossewabrandwag blamed Jan Smuts for bringing the vuilgoed (rubbish) of Europe to South Africa. The local Greek community helped integrate him into society.

Bizos did not go to school for his first two years in the country as he spoke neither English nor Afrikaans. He gained entry to the University of the Witwatersrand in 1949, where he met Nelson Mandela and undertook a 3-year Bachelor of Arts degree, followed by a three-year LLB law degree. It was during this time that he first became politically active, joining the students' representative council under the leadership of Harold Wolpe.

Bizos joined the Bar in Johannesburg in 1954. During the 1950s and 1960s he was counsel to a wide range of well-known people including Trevor Huddleston of Sophiatown.

At the Rivonia Trial from 1963 to 1964, Bizos was part of the team that defended Nelson Mandela, Govan Mbeki and Walter Sisulu. The accused were sentenced to life imprisonment, but spared the death penalty. Although it is sometimes said that he claims to have drafted Mandela's famous speech spoken at the trial, he says that his main contribution was to advise the use of the words "if needs be" before Mandela said that he was prepared to die. Bizos believed that this may have contributed to the avoidance of the death penalty, by having Mandela not appear to seek martyrdom. This trial saw the arrival of a group of human rights lawyers – Joel Joffe, Harry Schwarz, Arthur Chaskalson and Harold Hanson.

Bizos was counsel for the accused in at least 26 other prominent anti-apartheid trials and inquests. In 1969 he acted for the defence of Winnie Madikizela-Mandela and 21 others on charges of contravening the Suppression of Communism Act and Unlawful Organisations Act. Together with Arthur Chaskalson and Dennis Kuny, he also represented the NUSAS Five who were charged with furthering the aims of the African National Congress and communism in 1975.