The N-Dubz star-turned-X Factor judge will perform her debut solo single 'Young' during the ITV1 talent competition's live shows, The Sun reports.
Contostavlos told the paper: "I'm very excited performing my single for the first time on Britain's Got Talent. It's a huge show, with a massive amount of viewers, for my first live solo music performance.
"Of course, Simon will be on the panel watching, so I'm performing in front of the X Factor boss too!"
An insider claimed that Cowell was "excited" to have secured Contostavlos for the show and is keen for her to "hold her head high and put in a storming performance" following the leak of a sex tape featuring her last month.
Cowell defended Contostavlos through the controversy, stating that her X Factor job is safe and adding that he felt "very sorry" for her.
'Young' is released on April 29.
Watch a behind-the-scenes feature on the filming of Tulisa's 'Young' music video below: