"Yellow Submarine" is a song by the English rock band the Beatles from their 1966 album Revolver. It was also issued on a double A-side single, paired with "Eleanor Rigby". Written as a children's song by Paul McCartney and John Lennon, it was drummer Ringo Starr's vocal spot on the album. The single went to number one on charts in the United Kingdom and several other European countries, and in Australia, Canada and New Zealand. It won an Ivor Novello Award for the highest certified sales of any single written by a British songwriter and issued in the UK in 1966. In the US, the song peaked at number two on the Billboard Hot 100 chart.

The Beatles recorded "Yellow Submarine" during a period characterised by experimentation in the recording studio. After taping the basic track and vocals in late May 1966, they held a session to overdub nautical sound effects, party ambience and chorus singing, recalling producer George Martin's previous work with members of the Goons. As a novelty song coupled with "Eleanor Rigby", a track devoid of any rock instrumentation, the single marked a radical departure for the group. It was also the first time they had issued a single in the UK consisting of album tracks. The song inspired the 1968 animated film Yellow Submarine and appeared as the opening track on the accompanying soundtrack album.

In the US, the release of "Yellow Submarine" coincided with the controversies surrounding Lennon's "More popular than Jesus" remarks, which led some radio stations to impose a ban on the Beatles' music, and the band's public opposition to the Vietnam War. The song received several social and political interpretations. It was adopted as an anti-authority statement by the counterculture during Vietnam War demonstrations and was also appropriated in strike action and other forms of protest. Some listeners viewed the song as a code for drugs, particularly the barbiturate Nembutal which was sold in yellow capsules, or as a symbol for escapism. "Yellow Submarine" has continued to be a children's favourite and has frequently been performed by Starr on his tours with the All Starr Band.