"Bad Romance" is a song by American recording artist Lady Gaga. It is the lead single from her second studio album, The Fame Monster. The track was produced by RedOne and was inspired by the paranoia that she had felt while touring through the previous year. After the demo version of the song leaked, Gaga premiered the song at Alexander McQueen's Spring/Summer 2010 Paris Fashion Week show on October 6, 2009, followed by the release of the cover art. Composed in a similar tempo to her previous singles, "Bad Romance" features a bridge and a full-throated chorus. The song talks about exploring the joys of a bad romance while referencing Alfred Hitchcock films in some of the verses.

Contemporary critics gave positive reviews of the song with majority of them comparing the song to Gaga's second single "Poker Face". It has since reached number-one on the UK Singles Chart, Irish Singles Chart, Canadian Hot 100 and the Swedish, German, Austrian and Danish charts, while peaking at number two in countries such as the United States, Australia and New Zealand. The accompanying music video takes place in a white bathhouse where Gaga is kidnapped by a group of supermodels who drug her and then sell her off to the Russian Mafia for sexual slavery. The video received positive response for its treatment and innovation, critics noting more its craziness and symbolic plot.

Gaga has performed "Bad Romance" on a number of television shows including Saturday Night Live and Gossip Girl, as well as award shows such as the 2009 American Music Awards. It was the closing song of Gaga's The Monster Ball Tour. Rolling Stone ranked the song at position ten on their Best 25 Songs of 2009 list.