Mayhew was born on 19 May 1944 in Barnes, Surrey, where he was also raised. His height is not a product of gigantism, “I don’t have the big head”, but of a connective tissue disorder called Marfan syndrome. His maximum height was 7 feet 3 inches (221 cm).
Mayhew got his first acting job in 1976 when the producers of Sinbad and the Eye of the Tiger discovered him from a photograph in a newspaper article about men with large feet, and cast him in the role of the minotaur.
When casting his first Star Wars film, producer George Lucas needed a tall actor who could fit the role of the hairy alien Chewbacca. He originally had in mind 6-foot-6-inch (1.98 m) bodybuilder David Prowse, but Prowse chose to play Darth Vader. This led Lucas on a search which turned up Mayhew, who was working as an orderly and said that all he had to do to be cast in the role of Chewbacca was stand up.
Mayhew has played Chewbacca in five Star Wars films: the original trilogy (Star Wars, The Empire Strikes Back and Return of the Jedi), Star Wars: Episode III – Revenge of the Sith and Star Wars: The Force Awakens. He played the role in the 1978 television film Star Wars Holiday Special and in an appearance on The Muppet Show. He also recorded dialogue for the Star Wars: The Clone Wars Season 3 finale episode “Wookiee Hunt”.
Mayhew plays the role in commercials and in hospital appearances for sick children and has made numerous appearances as Chewbacca outside the Star Wars films. Mayhew as Chewbacca was honoured with a Lifetime Achievement Award at the MTV Film Awards 1997. He was additionally honoured at the release of the new PlayStation Portable where he dressed as Chewbacca and held up the new PSP slim version.
He has made other media appearances without the Chewbacca costume. He appeared on NBC‘s Identity, where his identity was based on the fact that he played Chewbacca and was a frequent guest in the early days of Slice of SciFi.
While Mayhew portrayed Chewbacca in Star Wars: The Force Awakens, he was not in Star Wars: The Last Jedi but was listed in the credits as ‘Chewbacca Consultant’. Mayhew retired from playing Chewbacca due to health issues. Joonas Suotamo, shared the portrayal of Chewbacca with Mayhew on Star Wars: The Force Awakens, and then replaced him in subsequent Star Wars films
Outside Star Wars, Mayhew has appeared in the 1978 horror film Terror, directed by Norman J. Warren. In the English version of Dragon Ball GT: A Hero’s Legacy, he provided the voice for Susha. He also appeared in Yesterday Was a Lie.
Mayhew has written two books for younger audience: “Growing Up Giant” which explains that being different is a strength instead of a weakness and anti-bullying book for children “My Favorite Giant”.
Mayhew lives with his wife Mary Angela (“Angie”) in Boyd, Texas and is a business owner. He became a naturalised citizen of the United States in 2005 at a ceremony in Arlington, Texas. In an interview with the Fort Worth Star-Telegram he joked that he did not get a medal at this ceremony either, a reference to the Star Wars scene in which Luke and Han get medals but Chewbacca does not. Mayhew noted in an MTV interview that although Chewbacca does not get a medal in the film, he does get the last line, when he roars.