The singer, who first announced her plans to go bald for charity 18 months ago, said, "Shaving my head for charity is something I've promised to do for a long time and Comic Relief has given me the opportunity to try and raise as much money as possible for good causes by doing it."
Jessie added, "This Red Nose Day I'll be shaving my head live on the night of TV. I won't deny that I'm nervous but I am also honoured to be part of this year's campaign."
The Voice judge, famous for her long dark tresses, will be snipping of her locks as part of the charity's 'Big Dare' initiative.
As well as Miss J's dramatic makeover, this Red Nose Day will see the likes of Mel C, Jack Dee, Greg James and Dara O Brian taking a trip down Africa's Zambezi River to Victoria Falls.
On top of all that, One Direction are releasing this year's official Comic Relief single, a cover of Blondie's mega hit One Way Or Another, AND official T-shirts have been designed by none other than Stella McCartney.
Before Jessie ditches her hair for good, let's have a quick glance over her best style and beauty looks.