I Want You (She's So Heavy) is a song by The Beatles, from their album Abbey Road. It was written by John Lennon (with some creative input from Yoko Ono), although it is credited as a Lennon/McCartney collaboration.

The song is an unusual Beatles composition for a variety of reasons, namely its length (nearly eight minutes), its disproportionately small number of lyrics (only seventeen different words are sung), its three-minute descent through the same repeated guitar chords (a similar arpeggiated figure appears in other Lennon contributions to the album, "Because" as well as McCartney's "Oh! Darling"), its hard rock sound, and for its instantaneous and unanticipated end. It is also one of the last songs that the Beatles mixed as a group, on August 20, 1969.

David Gates writes of the song, "The hypnotically repeated guitar figure in 'I Want You (She's So Heavy)' is suddenly, arbitrarily cut off, jolting us into embarrassed awareness that we've let a mere recording carry us away."