The BBC One series has already been renewed for a third series, but confessed she would be focusing on her career next Spring.
This year saw Jessie delay her new album and push back her tour in order to take part in the second series, but she won't be doing it again.
"If I can do another series then it would be great but if I can’t because of my schedule then so be it," Jessie said.
She explained: "I don’t think people realise it takes up a lot of my time. Everything happens for a reason.
“I don’t know what I’ll do – at the moment I’m focusing on this series.”
Jessie's decision to leave could also see other coaches bow out of the show too.
Will.i.am recently claimed he would only be back if everyone else was, saying: "It would be hard to do it without the others. I can't think about doing it with someone else. It would be weird.
"I know to look to the left when I'm having a bad day and Jessie will pull some weird-ass face and cheer me up. I know Tom's going to be all silver berry cool and Danny's an inspiration."
And Sir Tom Jones echoed Will's comments, saying he would have to wait to see who the other coaches were before agreeing to a new series.