The 'Party Girl' group are in the studio working on their sixth album and are hopeful they can convince the 'Price Tag' singer to join them on a song.
Guitarist Danny Jones told the Daily Star newspaper: ''It's hard to know what direction the next album will take. It would be cool to get Jessie J on there. I think she'd be amazing.''
McFly - which also includes Harry Judd, Dougie Poynter and Tom Fletcher - are also excited about the record, because they are writing it all themselves, and are excited to be in full creative control.
Tom said: ''It will be the first album where it's 100 per cent exactly how we envision the album to be.''
The band are also about to embark on a greatest hits tour, and Danny, 26, said he's amazed when he looks back at how much some of their tracks have changed.
Referring to their debut single, '5 Colours in Her Hair', he said: ''You can make things different each night.
''For example, 'Five Colours' has changed so much over the years. The way we play it live now is like some crazy Green Day version.''