Former boy band 'N Sync are being sued over claims they plagiarised a song on their 2001 album Celebrity.

In a lawsuit filed on Monday in Las Vegas Federal Court, Troy Alexander alleges he met the band's record label Jive in 1990 and gave them a demo tape for his song Up Against The Wall.

According to documents obtained by TMZ.com, the band - Lance Bass, JC Chasez, Joey Fatone, Chris Kirkpatrick, and Justin Timberlake - released a track with the same title "substantially similar" to the demo.

A spokesperson for Jive records reveals they are not aware of the claim and have not been served with any papers.

'N Sync split in 2002.