She died of cancer on June 6 at New York's Mount Sinai Hospital, John Barlow, spokesman for her husband, actor-filmmaker Mel Brooks, said.
Bancroft was awarded the Tony for her Broadway portrayal of poor-sighted Annie Sullivan, the teacher of Keller, who was born deaf and blind. Keller went on to invent Braille, a method that helps the visually impaired read. She repeated her portrayal in the film version.
Despite her Academy Award and four other nominations, The Graduate overshadowed her other achievements. Actor Dustin Hoffman delivered the line that went on to become unforgettable when he realised his girlfriend's mother was coming on to him in a hotel room: 'Mrs Robinson, you're trying to seduce me, aren't you?'
In an interview she gave in 2003, Bancroft complained, 'I am quite surprised that, with all my work -- and some of it is very, very good -- nobody talks about The Miracle Worker. We're talking about Mrs Robinson,' she said. 'I understand the world. I'm just a little dismayed that people aren't beyond it yet.'
The actress was signed by Twentieth Century-Fox in 1952. She had been acting in television as Anne Marno (her real name is Anna Maria Louise Italiano), but it sounded 'too ethnic' for movies. The studio gave her a choice of names. She picked Bancroft 'because it sounded dignified.'