The 'Firework' singer was named Ultimate International Music Star, while Gemma was given the Ultimate Film Actress accolade at the ceremony at London's Banqueting House in Whitehall.
Though the ceremony recognises the achievements of women, two men were also honoured.
Speaking at the event, Dizzee said: "There's a lot of hotties here, Kelly Brook told me she was single, there's a lot going on!"
The 'Dance Wiv Me' rapper has earlier posed on the red carpet with 'Piranha 3D' actress, who also praised Dizzee for his dapper appearance.
She said: "He does look good. He's very handsome too and very sweet and charming."
Plus-sized model Crystal Renn was named Ultimate Catwalk Queen, while 'Mad Men' actress Christina Hendricks was named Ultimate US TV Actress.
Girls Aloud star Nicola Roberts took home the Ultimate Fashionista title, and was joined at the star-studded ceremony by her bandmate Kimberley Walsh, who was one of the judges who selected the non=celebrity winners.
Cosmopolitan's Editor Louise Court - who headed the group of judges - said: "I have been honoured to once again celebrate the achievements of such deserving people. The women that have been recognised tonight are truly inspirational and all embody the 'fun and fearless' spirit of the magazine."
Cosmopolitan Ultimate Women Of The Year Awards 2010, list of celebrity winners:
Ultimate TV Presenter - Christine Bleakley
Ultimate Theatre Star - Sheridan Smith
Ultimate UK Music Star - Alexandra Burke
Ultimate UK TV Actress - Karen Gillan
Ultimate International Music Star - Katy Perry
Ultimate Fashionista - Nicola Roberts
Ultimate Catwalk Queen - Crystal Renn
Ultimate Celebrity Who Made Us Care - Fearne Cotton
Ultimate Man of the Year - Dizzee Rascal
Ultimate Film Actress - Gemma Arterton
Ultimate Hottie - Mark Salling
Ultimate US TV Actress - Christina Hendricks
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