After the news was announced on on Gaby Roslin's BBC Radio London show, Emma explained, “I absolutely love watching Strictly every weekend and I can’t believe that I’m getting the chance to be on this series.
"I know it will be such an amazing experience from start to finish. I can’t wait for the dancing and the fabulous outfits!”
The 33-year-old is a socialite, and became a Viscountess after marrying Ceawlin Thynn, Viscount Weymouth, in 2013.
She now works as a chef, launching her own 'Emma's Kitchen' project at Longleat Estate, in which she is the chatelaine, in 2015.
“I have a real passion for food – I love to cook for my family and friends and relish any opportunity to entertain. It has been my ambition, for some time, to bring the heart of the house back to life," she said.
"Emma’s Kitchen is the result of that ambition - a space for me to share my passion and some of my favourite recipes."
In addition to cooking, Emma is also a contributing editor to British Vogue, and has modelled and served as an ambassador for a series of fashion brands.
Strictly has not been Emma's first foray into television, having previously appeared on James Martin's Saturday Morning TV show with ITV.
She joins footballer David James, comedian Chris Ramsey, EastEnders star Emma Barton, social media star Saffron Barker, actor Catherine Tyldesley, BBC Breakfast's Mike Bushell and CBBC presenter Karim Zeroual in the line-up for series 17.
Strictly Come Dancing returns later this year on BBC 1.