"Sex on Fire" is the first single released from American rock band Kings of Leon's fourth studio album, Only by the Night.

The song gave Kings of Leon their first number-one single in Australia, Finland, Ireland, and the United Kingdom, charting at the top spot on digital downloads alone in the latter country, before its physical release.

[8][9] The song was written about lead singer Caleb's then-girlfriend (and now-wife), model Lily Aldridge.

Digital Spy rated the song four stars out of five, describing it as "a truly stirring single that will be a definite highlight on their winter arena tour".

However, Caleb Followill originally thought the song was "terrible";[14] according to Spin Magazine, it was almost ditched during recording.

[16] In 2016, Johnny Borrell of Razorlight called this song "the apex, death and afterlife of landfill indie all in one go" and noted its similarity to Stereophonics's "Dakota" from 2005.

[17] In the United Kingdom, "Sex on Fire" entered the official UK Singles Chart at number one on September 14, 2008 ― for the week ending date September 20, 2008 ― and went on to an unbroken 42 weeks on the chart, only dropping out due to the surge in sales of Michael Jackson titles immediately after his death, but after a two-week absence it was back for another 37 weeks, re-entering the top 10 of the UK Singles Chart at number six in September 2009.

As of February 2011, the song had been on the chart for 60 weeks, a huge effort for a single that did not reach the top 20.