"Leave (Get Out)" is a song by American singer JoJo from her self-titled debut album. It was released as the album's lead single on February 24, 2004. Produced by Danish production duo Soulshock & Karlin, it became an international hit, reaching number 12 on the US Billboard Hot 100 and number two in the United Kingdom, Australia, New Zealand, and on the European Hot 100 Singles. It also became a top five hit in Belgium, Ireland, the Netherlands, and Switzerland. The single was certified gold by the Recording Industry Association of America (RIAA) on October 25, 2004. When the single reached number one on Billboard's Pop Songs chart, JoJo became, at age 13, the youngest solo artist to have a number-one single in the United States.

JoJo has expressed her displeasure with the song, and most of her self-titled album, for its overall pop sound. However, she is grateful that it put her on the musical map. When she would perform the song at her most recent concerts, she would arrange it to the point of being almost unrecognizable, adding jazzier instrumentation to the verses and heavier guitars or double-kick drumming to the bridge. The song appears in the 2004 PlayStation 2 karaoke game Karaoke Revolution Volume 3 and Singstar Pop Hits. On her 2011 tour, JoJo would open her set with her band playing the intro of Dropkick Murphys "I'm Shipping Up To Boston" which would then segue into "Leave".

"Leave (Get Out)" was written by Soulshock, Kenneth Karlin, and Alex Cantrell, while production and arrangement was helmed by Soulshock. The song was recorded at Soulpower Studios and Westlake Studios in Los Angeles, California. Soulshock also mixed the song at Soulpower Studios and provided all the instruments with Karlin. The guitars, however, were performed by Eric Jackson and Sean Hurley. "Leave (Get Out)" was released as JoJo's debut single on February 24, 2004, through Blackground Records, via digital download and physical single. The single released in the United States included the song and a b-side, "Not That Kinda Girl". On June 21, 2004, the song was released to European markets in CD and maxi single formats. The song was released in the United Kingdom and Ireland on August 30, 2004 as a CD single and digital download.

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