She joins Gary Barlow, Tulisa Contostavlos and Louis Walsh on the panel for all three days of auditions.
They will take place at Event City from Tuesday, June 5 to Thursday, June 7.
The former Spice Girl told Digital Spy: "I'm so, so, so excited to be a guest judge for The X Factor in Manchester.
"Being a Northern girl I believe there's lots of amazing talent in the North of England. Go the Northerners and don't let me down!
"I am coming to find the winner! I love my job as a judge on The X Factor Australia but it will be great to sit on the panel in the UK.
"Britain is and always will be my home and first love."
Guest judges on the new series so far have included Leona Lewis, Rita Ora and Mel B's former bandmate Geri Halliwell.
Halliwell previously claimed that it would be "disloyal" of Mel B to appear while she is pursuing the role herself.
The 39-year-old apparently failed to make a good impression when acting as a guest judge for auditions in Liverpool.
