The programme will feature 10 footballers' wives and girlfriends designing and running a fashion boutique in London, overseen by an as-yet unnamed mentor.
Diet Coke will have rights to the content across magazines, radio, online and mobile, as well as sponsorship of www.itv.com/WAGS. Ad agency VCCP will be responsible for the creative.
Last month Coleen McLoughlin, the girlfriend of Manchester United star Wayne Rooney, signed up to become the face of Diet Coke. Rooney already has a contract with Coke Zero.
The sponsorship is part of Diet Coke's strategy of refocusing on its core female audience. The brand was the top-selling soft drink in the year to April, with sales of £230m-£235m, according to TNS Worldpanel.