He was considered the most successful music producer ever, cited in the Guinness Book of Records for having more than 50 No. 1 hit records over five decades in the United States and Britain alone.
He helped score, arrange, and produce many of the band's biggest hits, including "I Wanna Hold Your Hand," "A Day in the Life", “Yesterday”, "Eleanor Rigby" and "Love Me Do".
"I’m so sad to hear the news of the passing of dear George Martin," Beatle Paul McCartney said in a statement on Wednesday.
"If anyone earned the title of the fifth Beatle it was George."
A statement from Martin's family confirmed he had died peacefully at his home on Tuesday evening.
Earlier, Ringo Starr, the Beatles' drummer, had announced his death on Twitter: "God bless George Martin peace and love to Judy and his family... George will be missed."
Starr followed the message by posting a black and white photo of the Fab Four with Martin, saying "Thank you for all your love and kindness George."
Martin served as producer, collaborator and mentor to Beatles John Lennon, George Harrison, McCartney and Starr.
Lennon was shot dead in New York in 1980. Harrison died of cancer in 2001.
Tributes from the music world poured in on Twitter. "RIP to my musical brother George Martin. We were friends since 1964, & I am so thankful 4 that gift," said American music producer Quincy Jones.
Lenny Kravitz said: "The legends are really going home!" Boy George said: "George Martin. Gentleman and legend", while Mark Ronson said Martin was "the greatest British record producer of all time."
Britain's Prime Minister David Cameron said on Twitter: "George Martin was a giant of music - working with the Fab Four to create the world's most enduring pop music."
During his seven-decade career in the music industry, Martin produced almost all of the Beatles' recordings and also worked with Gerry & the Pacemakers, Shirley Bassey, Cilla Black, Jeff Beck, America, Cheap Trick and other acts.
Martin started work at Abbey Road Studios in 1950 producing records for EMI's Parlophone label.
He was noted for his comedy recordings with the likes of Peter Sellers, Spike Milligan and Beyond the Fringe and got his first Number 1 with The Temperance Seven in 1961. He signed The Beatles in 1962
The young band members were rough around the edges, but Martin saw their commercial promise and with them helped revolutionize the art of popular music recording.
His 1979 autobiography, "All You Need Is Ears", chronicles his discovery of the Beatles and their creative process.
Martin was knighted in 1996. In 2006, working with his son, Giles Martin, he helped develop the Beatles-inspired Cirque du Soleil show "Love" in Las Vegas, which went on to reap his two most recent Grammys.
(Reporting by Victoria Cavaliere in Los Angeles and James Davey in London, Editing by Ralph Boulton)
I read the news today, oh boy. Sir George Martin, The Beatles' record producer, passed away at age 90. I wondered, would the Beatles have accomplished so much without him? Sir Paul McCartney paid tribute to Martin, calling him a "true gentleman and like a second father to me." Martin gave them their big break in 1962 when he signed the Beatles to Parlophone/EMI, and he went on to produce the band's 13 albums between March, 1963 and May, 1970.
Martin was a classically trained musician, but was enthralled by the Beatles' creativity. He was much more than a mere overseer, Martin was an active participant with the Beatles. He wrote the string arrangements accompanying Paul McCartney on "Yesterday" and "Eleanor Rigby." Martin composed and orchestrated parts of "A Hard Day's Night," "Sgt. Pepper's Lonely Hearts Club Band," "Magical Mystery Tour" and "Yellow Submarine" albums. Martin and the Beatles together were creating new ways of recording music.
I saw Martin at a book signing event at Barnes & Noble five years ago. He was a soft spoken man. I remember the way he delighted the crowd with tales of Beatles sessions. But more than anything else I was taken by his little tidbit about what happened when the Beatles got the munchies in the middle of the night -- they would sometimes eat other studio employees' cookies and write them notes apologizing for the misdeed! Martin struck me as a man who lived exactly the life he wanted and was thankful for it.
Martin worked with Pete Townshend on the musical stage production of "The Who's Tommy," which opened on Broadway in 1993. He also worked with Elton John and produced hit records for Jeff Beck, Sting, Elvis Costello, Cheap Trick, America and Paul McCartney.
Martin produced two of the best James Bond themes. The first was "Goldfinger" by Shirley Bassey in 1964. The second in 1973 was "Live and Let Die" by Paul McCartney and Wings.
George Martin broke the mold. He set a high standard for rock record producers and there will never be another like him. Goodbye Sir George.