The '80s popstar, who is a close friend of Simon Cowell, was believed to have signed a deal to enter the jungle worth £30,000.
However, the Daily Star is reporting that the 'So Macho' singer has now withdrawn from the series at the final hour.
Sinitta was supposed to be flying over to Australia at the start of this week to join famous faces including TOWIE's Mark Wright, comic Freddie Starr and McFly's Dougie Poynter.
A rep for Sinitta told the newspaper: "She would have been hilarious but her phobias cause panic attacks."
Pat Sharp is rumoured to be the celebrity on standby if any one of the contestants drop out of the show.
I'm a Celebrity kicks off on Sunday at 9pm on ITV1.
> More 'I'm a Celebrity' news