Cassie Sumner (* 13 January 1983 in Kent) is an English glamour model and WAGs Boutique star.
She starred in ITV1's 2004 TV show, Poor Little Rich Girls.

As a model, she has notched-up several appearances on ’Page 3’ and has starred in photo shoots and features for publications including OK! magazine, Playboy, Ice, Nuts, Zoo Weekly, Loaded, Fast Car, Max Power, Front, Penthouse, New, The Express, Daily Star and News of the World. Cassie was named as one of Britain’s Top 20 Top models in top-selling lads’ magazine, Nuts. She was also named by FHM magazine as one of Britain’s Hottest 100 Girls.

Cassie has also acted/starred in several TV shows, like the 13-week reality fashion TV series, WAGs Boutique (ITV and ITV2), which aired from January - April 2007, as well as Sky One's Dream Team, Cassie's Crib (Sky) Al Murray's Happy Hour (ITV). She's also been interviewed on numerous radio stations in 2007, such as Heart FM and Radio Five Live.

She was a pupil at St John Fisher Secondary School in Chatham, Kent and finished school with 1 GCSE.

In her private life Cassie has dated comedian Russell Brand. After splitting from Brand, Cassie sold a kiss and tell to a tabloid newspaper, detailing the bizarre nature of her relationship with the former Big Brother's Big Mouth presenter, in particular his apparent peculiar behaviour. In 2006 Russell used the kiss and tell as part of his act to discredit many of the claims Cassie had made. His 'Russell Brand Live' DVD features this part of his act. She also claimed to have had a relationship with Chelsea star Michael Essien, an allegation which he later denied in the newspapers. Cassie was later revealed an escort by the News Of The World, selling her body for £1000 an hour mostly to Arab clients.