Reports of Walsh joining the dancing competition emerged last month, with sources claiming she was "thrilled" to join the programme.
The news has now been confirmed by the makers of Strictly Come Dancing, who tweeted from the show's official Twitter account today (September 8): "Kimberley Walsh joins Strictly Come Dancing! A rumour no longer just the 'sound of the underground'."
Westlife's Nicky Byrne and Daybreak's Richard Arnold have also been confirmed, with Denise Van Outen also reportedly having signed up.
Children's TV icon Johnny Ball, cricket legend Michael Vaughan, Fern Britton and Jerry Hall are among the other rumoured celebrities taking part this year.
The Girls Aloud singer posted photos of herself and dancer Anton du Beke on her Twitter account, though it's unclear whether he will be her partner on the series.
Walsh is due to reunite with her Girls Aloud bandmates at the Royal Variety Performance later this year, to celebrate the tenth anniversary of their win on ITV reality show Popstars: The Rivals.
Strictly 2012 Judges & Hosts - Pictures: