Brian Samuel Epstein (September 19, 1934 – August 27, 1967) was a British businessman, best known as the manager of the Beatles.

Epstein's father owned a furniture store where Paul McCartney's family bought a piano. Epstein's father put him in charge of the ground floor of the newly opened Northern England Music Stores (NEMS) store on Great Charlotte Street. Eventually, a second store was opened at 12-14 Whitechapel, and Epstein was put in charge of the entire operation. On August 3, 1961 Epstein began writing a regular music column in Mersey Beat.

Epstein first noticed the Beatles when he heard them backing Tony Sheridan on a single. Epstein and friend, Alistair Taylor, went to see the band perform at the crowded Cavern Club, which was just down the street from his store. Epstein said of the performance: "I was immediately struck by their music, their beat, and their sense of humour on stage. And even afterwards when I met them I was struck again by their personal charm. And it was there that really it all started..."

It was decided that Epstein would manage the band during a meeting on December 10, 1961. The guys then signed a five-year contract with Epstein at Pete Best's house on January 24, 1962. Epstein did not sign the contract, giving the Beatles the option of getting out of the contract at any time.

Although not known for making good business decisions or deals, Epstein was a major force behind the band's early appearance and success. When Epstein found the band, they were wearing blue jeans and leather jackets, performing rowdy rock'n'roll shows. He encouraged them to wear suits and clean up their stage performance. He also asked them not to smoke on stage, and encouraged the famous synchronised bow at the end of their performances. Although this image didn't last for long, the fairly clean-cut appearance (with the exception of the "mop top" hairstyles) helped the band get accepted by the public.

After being rejected by every major record label in England, Epstein was eventually able to get the band signed to EMI's small Parlophone label. Epstein visited a local HMV store to have the Beatles' demo tapes copied in its recording studio. An HMV technician named Jim Foy heard the songs and told EMI's George Martin about them. Martin then agreed to meet with Epstein's new band and scheduled an audition. After their first rehearsals with Martin, John Lennon, Paul McCartney and George Harrison asked Epstein to fire drummer Pete Best, who was later replaced by Ringo Starr. Brian Epstein was rumoured to have been infatuated with John Lennon, even to have had an affair with him in Spain while on holiday in 1963, but Lennon later denied these rumours; a ficticious account of this was portrayed in the film The Hours and Times.

In October 1964, Epstein's autobiography, A Cellarful of Noise, was published, cowritten by Beatles publicist Derek Taylor.

In addition to managing the Beatles, Epstein also managed Gerry & the Pacemakers, Billy J. Kramer & The Dakotas, The Fourmost and Cilla Black.

Epstein died of a drug overdose, likely from some sort of sleeping pills, on August 27, 1967. The death was officially ruled accidental, although it has often been speculated that it was a suicide. Epstein managed every aspect of the Beatles' career. When he died the difference was immediately noticeable and their business affairs began to unravel.