Lord Attenborough was in a stable condition yesterday after suffering a fall at his home, a hospital spokesman has said.
The 85-year-old actor and director was forced to pull out of a plaque-unveiling ceremony after the accident.
A spokesman for St George's Hospital in Tooting, south-west London, said: "Richard Attenborough suffered a fall at his home and is receiving care at St George's Hospital.
"He is currently in a stable condition."
Lord "Dickie" Attenborough had been due to honour Brief Encounter star Dame Celia Johnson on Thursday, the centenary of her birth.
A spokeswoman for the event said: "He had a fall and he wasn't able to do it.".
She said the accident happened earlier this week.
The English Heritage blue plaque was placed at 46 Richmond Hill in Richmond upon Thames, Surrey, where she was born and lived until 1924.
Born in Cambridge in 1923, Lord Attenborough has championed the British film business through its triumphs and trials for more than 60 years as actor, Oscar-winning director and prolific movie-maker.
Gandhi is the highlight of his career, clinching eight Oscars, including best film and best director.
His breadth of canvas and concern for detail were at their most impressive here, with Attenborough displaying an uncanny knack to control some 400,000 extras at the recreation of Gandhi's funeral.
As an actor he was respected enough for top directors Satyajit Ray and Steven Spielberg to lure him out of self-imposed retirement to appear respectively in The Chess Players and the blockbuster Jurassic Park.
His highly emotional and effusive character is one of the most lampooned in the art world, where he is known as the "original luvvy" who is easily moved to tears.
His public image belies a steel-like determination that took him from a powerful character actor in films such as Brighton Rock and 10 Rillington Place to director of conventional pieces such as Young Winston and A Bridge Too Far and ultimately Gandhi and Cry Freedom.
Tragedy struck on Boxing Day 2004 when his elder daughter Jane Holland her daughter, Lucy, and her mother-in-law, also named Jane, were killed in the south-Asian tsunami.
Lord Attenborough lives in Richmond upon Thames.
He married the actress Sheila Sim when he was 21. His son Michael was born in 1949, followed by daughters Jane and Charlotte.
Michael is artistic director of the Almeida Theatre in Islington, north London, and Charlotte Attenborough is an actress.
Lord Attenborough struck up a friendship with Diana, Princess of Wales, after Prince Charles asked him to help her write speeches.
He is the older brother of TV wild life presenter Sir David Attenborough.