Davina, 53, was filming the third episode of the ITV series when she made the jaw-dropping admission.
Sausage was about to perform for the second time as they were in the bottom two.
Just before the hidden celebrity began to sing, Davina suddenly shouted: "I love sausage!"
Realising what she had said, the presenter pulled a funny face which left viewers in fits of giggles.
One said: "The fact @ThisisDavina just said 'I love sausage' on #TheMaskedSinger and her face after have me in tears. Same girl. Same.
While another wrote: "@ThisisDavina when Davina proudly says she loves sausage, on the masked singer then realises what she's said, I almost choked on my wine."
A third added: "Davina love, you’re not alone. We all love a bit of sausage".
"@ThisIsDavina I love the fact you are not ashamed to say 'you love sausage'", penned a fourth.
The Masked Singer viewers were gobsmacked as another celebrity removed their mask during Saturday's episode.
Swan was revealed to be none other than former EastEnders star Martine McCutcheon.
The judging panel made up of Jonathan Ross, Rita Ora, Davina McCall and Mo Gillian were aghast as they saw the Love Actually actress unveiled at the end of the show.
Sausage and Swan were in the bottom two, so competed to make it through to the next round.
Swan sang a version of Black Velvet by Alannah Myles, while Sausage belted out En Vouge's Don't Let Go.
The panel plumped to eliminate Swan from the competition after much consideration.
The Masked Singer airs Saturdays at 7pm on ITV.