In 1967, the Beatles released Magical Mystery Tour, which featured previously uncollected songs as well as tunes from the band's television special of the same title. Included on the album is Harrison's characteristically quirky "Blue Jay Way," which features manipulated vocals and unusual instrumentations. Harrison, however, was not the only member of the Beatles to indulge in radical expression. Lennon, for example, demonstrated his prowess as a pioneering songwriter with both "I Am the Walrus," which ends in a plethora of chants and dialogues, and the psychedelic "Strawberry Fields Forever," which culminates in an orchestral flourish. By this time, the Beatles had undergone significant changes. They had exchanged their mop-top haircuts and matching suits for the long hair and colorful clothes indicative of Sixties fashions, and they would eventually forsake fashion entirely and sport facial hair. In addition, they had largely abandoned the primitive rock of their early days in favor of complex arrangements and elaborate musical structures. But they had also grown apart as musicians. McCartney, perhaps the most accessible of the Beatles songwriters, had begun to surpass Lennon in influence within the band. Lennon, meanwhile, became increasingly political and experimental, and Harrison began to demonstrate renewed interest in more conventional rock ballads.

The band's growing eclecticism is evident in The Beatles ,their 1968 release usually referred to as the "White Album." The recording ranges from McCartney's "Back in the USSR," which recalls the music of the Beach Boys, to Lennon's amiable "Revolution," and it also features both acoustic tunes such as "Rocky Raccoon" and basic rock songs such as "Helter Skelter." Harrison's contributions include "While My Guitar Gently Weeps," which features a solo by his close friend, eminent guitarist Eric Clapton. But as Harrison told Dan Forte in a Guitar Player interview, "It was my guitar that was gently weeping—Eric just happened to be playing it."

The Beatles determined to film themselves making their next recording. But the ensuing project became most memorable as a document of the increasing tension within the band, and it reveals the increasing presence of Lennon's lover, Yoko Ono. After ending the film project, the Beatles reconvened with producer George Martin for Abbey Road, which included two of Harrison's most popular songs, "Here Comes the Sun" and "Something." This album marked the quartet's last work as collaborating musicians. The next year saw the release of Let It Be, a collection of songs—reworked by producer Phil Spector—from the documentary film project.

After the Beatles ceased working together, Harrison, who had amassed a sizeable collection of songs, released All Things Must Pass, a three-record work in which songs such as "My Sweet Lord" and "Awaiting on You All" demonstrate his affinity for mixing rock and religion. All Things Must Pass, which also generated such popular songs as "What Is Life" and "Wah Wah," topped the Billboard charts in early 1971. Later that year, Harrison organized benefits to raise funds for famine victims in Bangladesh. These concerts, featuring Harrison and such artists as Ringo Starr, Eric Clapton, Leon Russell, and Bob Dylan, resulted in another three-record release, The Concert for Bangladesh, and a film of the same title.