"Long, Long, Long" is a song by the English rock band the Beatles from their 1968 album The Beatles (also known as "the White Album"). It was written by George Harrison, the group's lead guitarist, while he and his bandmates were attending Maharishi Mahesh Yogi's Transcendental Meditation course in Rishikesh, India, in early 1968. Although Harrison later stated that he was addressing God in the lyrics, it is the first of his compositions that invites interpretation as both a standard love song and a paean to his deity.

"Long, Long, Long" originated during a period in which Harrison emerged as a prolific songwriter, coinciding with his return to the guitar after two years of studying the Indian sitar. He based the chord pattern on "Sad Eyed Lady of the Lowlands" by Bob Dylan, while the song's understated arrangement partly reflects the influence of the Band's 1968 album Music from Big Pink. The Beatles recorded it in London towards the end of the White Album sessions, which were marked by acrimony among the band members in the fallout to their experiences in Rishikesh. An ambient and meditative ballad, it ends with a partly improvised segment that was inspired by the sound of a wine bottle vibrating on a speaker in the studio.

"Long, Long, Long" has received praise from several music critics. On release, William Mann of The Times rated it the equal of the album's best Lennon–McCartney compositions; Ian MacDonald later described it as Harrison's "touching token of exhausted, relieved reconciliation with God" and his "finest moment on The Beatles". Elliott Smith and Jim James are among the other artists who have recorded or performed the song.