Jo O'Meara, who has previously starred at the festival, will head the bill at this year's event in Sir Nigel Gresley Square on August 20.
The singer enjoyed huge chart success with the pop band during the late 90s and early 2000s with dancefloor fillers such as Reach, Don't Stop Movin' and Bring It All Back.
During their career, the band, which also featured Tina Barrett, Paul Cattermole, Jon Lee, Bradley McIntosh, Hannah Spearritt and Rachel Stevens, enjoyed five top 20 albums and 12 top ten singles including four number ones.
Following S Club, she was embroiled in controversy in 2007 when she was at the centre of a race row during her appearance as contestant on Celebrity Big Brother when she and fellow stars Jade Goody and Danielle Lloyd were found making racist comments against Shilpa Shetty, the eventual winner of the show.
Pride, which celebrates its 10th anniversary this year, will run from 1pm to 10pm and will also include a string of other musical performances, drag performers and other entertainments.
Full details are available at http://www.doncasterpride.co.uk/