The massive spoiler was dropped during last night’s launch show.
As host Emma Willis, 41, revealed the 70-year-old would be the first to enter the house, Ann’s VT started rolling, where the secret was revealed.
When asked how she would deal with living with so many different people, Ann said: "I do live alone, so ask me to share with 15 other people and yes that might be a bit of a challenge.”
Viewers were quick to notice Ann had let slip the number of men that would be joining the contest.
CHANNEL 5Ann Widdecombe revealed a huge secret on the show
“Ann accidentally tells us there’ll be seven men going in at some point #CBB,” wrote a fan.
Last night also saw Rylan Clark-Neal name the first male contestant who would be joining the line-up.
The 29-year-old presenter divulged on Celebrity Big Brother’s Bit On The Side that it would be ex-footballer John Barnes.
CHANNEL 5Ann Widdecombe was the first to enter the Celebrity Big Brother House
CHANNEL 5John Barnes will be joining the show on Friday
The house is currently home to just female celebrities in a twist on the usual format as the series marks 100 years since women won the right to vote in the UK.
Ann is currently joined by Rachel Johnson, Ashley James, India Willoughby, Malika Haqq, Maggie Oliver, Jess Impiazzi and Amanda Barrie.
Celebrity Big Brother continues tonight at 9pm on Channel 5.