The 39-year-old star will judge the singing reality show along with Simon Cowell, Louis Walsh and Cheryl Cole, who is returning after leaving in 2012, reported Daily Mirror.
"I'm so excited to be joining The X Factor - I loved being a guest judge back in 2012," said Mel B.
"I've always thought honesty is the best policy when being a judge and that's what I'm going to bring more of this year, whether it's spotting an incredible singer, giving someone a reality check or debating with Simon over who's got it wrong! Now I can't wait to get started and find some amazing talent," she said.