Taylor Swift has received death threats following her alleged romance with Harry Styles.

The 22-year-old was targeted by angry One Direction fans on Twitter after it was reported that the two pop stars were dating last week.

A group calling themselves Directioners used the social networking site to vent their fury over the pair's supposed relationship.

"I'll murder Taylor Swift. She will not date my Harry," one fan fumed according to British newspaper The Sun.

"If u dating my harry, I kill u (sic)," another user added.

The American country singer met Styles in March and the pair enjoyed a brief romance, before splitting shortly after.

Swift went on to date Conor Kennedy, while 18-year-old Styles started a relationship with model Emma Ostilly.

Swift and the teenage heartthrob sparked rumours of a reconciliation after being spotted together in Los Angeles.

Actor Mario Lopez took to his US radio show on Friday and confirmed the pair were dating, claiming Harry had hinted to him that he and the blonde beauty were more than friends.

It's not the first time fans of One Direction have used the internet to target girls associated with the band.

Model Edie Campbell quit the site after nasty messages, following a photoshoot with Harry, Zayn Malik, Louis Tomlinson, Liam Payne and Niall Horan.

- © Fairfax NZ News