The former Spice Girl was forced to miss Saturday evening's episode through illness but producers have confirmed she is well enough to appear on tonight's finale, where the winner will be crowned.
A statement from X Factor said: "Mel B is back on #XFactor tonight. After the hospital discharged her & following medical advice Mel is deemed well enough for the show.
"We're delighted to have her back."
No details have been given about Mel's illness.
On Saturday night's show, she was replaced by former X Factor judge Tulisa, who stood in for her at the last minute.
Tulisa was there to support Mel's last remaining contestant Andrea Faustini, who was in the final three. Unfortunately for him, he was eliminated on Saturday night, narrowly missing a spot in tonight's grand finale.
Tonight, Fleur East and Ben Haenow will battle it to be crowned winner of X Factor series eleven. Both were mentored by Simon Cowell.
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