"Sweetest Thing" is a song by Irish group U2. It was originally released in 1987 as a B-side on the "Where the Streets Have No Name" single. The song was later re-recorded and re-released, as a single in October 1998 for the U2 compilation album, The Best of 1980-1990.

The song was reportedly written by Bono as an apology to his wife Ali Hewson for having to work in the studio on her birthday during The Joshua Tree sessions. At Alison's request, profits from the single went to her favoured charity, Chernobyl Children's Project International.

A version by New York gospel choir, The New Voices of Freedom, appears on the soundtrack to the 1988 Bill Murray film Scrooged. It was recorded following U2's performance of "I Still Haven't Found What I'm Looking For" with the choir at Madison Square Garden, which appears on the band's 1988 album Rattle and Hum.

To promote the release of the single in 1998, Island Records distributed "Sweetest Thing" chocolate bars, wrapped to look like the single, throughout Europe. They have become a very valuable collectors item among U2 fans during the 2000s. The song reached #1 in both Canada and Ireland, #3 in the UK, #6 in Australia, #63 on the Billboard Hot 100, #9 on the Modern Rock Tracks chart and #31 on the Mainstream Rock Tracks chart in the United States.