Kelly, 40, looked gorgeous as she smouldered for the camera in the transparent ensemble, which featured a white embellished pattern all over the material.
The Heart FM's curves took centre-stage in the racy dress, which had no sleeves and a criss-cross design down the back, ensuring maximum skin was on show.
Kelly's hourglass proportions were highlighted by the skintight material, as her fans rushed to compliment her on the gorgeous throwback snap.
Letting her brunette hair fall behind her back, and keeping her make-up simple, Kelly looked beautiful as she smiled for the camera.
One fan wrote: "You're so beautiful."
Another added: "You're looking great for the Oscars."
A third chipped in: "Most amazing woman in the world."
A fourth wrote: "This picture of Kelly is a vision of beauty."
Kelly wasn't the only one to post a throwback picture from their appearance at the Oscars, as The Masked Singer judge Rita Ora reminisced about the 2019 ceremony, where she performed.
The blonde singer wore a black and white strapless dress with long sleeved black gloves as she performed Grateful on stage.
Rita's cleavage took centre-stage under the plunging neckline as she scraped her hair back to let her figure do the talking.
She captioned the pictures: "Performing my song ‘Grateful’ at the Oscars the year it was nominated will remain a highlight of my career!
"Good luck and congratulations to all the nominees tonight. I hope you enjoy my Prospero Tequila that’s inside the Nominee Gift Bags."
The hotly anticipated Oscars 2020 saw plenty of jaw-dropping talent win awards, and Parasite were the big winners of the night.
Director Bong Joon-ho's movie took home four awards, including Best Picture.
As the first film not in the English language to win this iconic accolade, the picture made cinematic history.
Parasite was victorious over films like 1917, Once Upon a Time in Hollywood, Marriage Story, The Irishman, Little Women, Joker, Ford V Ferrari and Jojo Rabbit.
Joaquin Phoenix was victorious with the Best Actor award for Joker, while Renee Zellweger won Best Actress for Judy.