Kate Stanners, who took over the creative hotseat at Saatchi & Saatchi three months ago, joins the film jury, while Ed Morris, who assumed a similar role at Lowe last autumn, will help judge press and outdoor entries.
Morris will be joined on the press jury by Gerry Moira, the former Publicis executive creative director who took command of Euro RSCG London's creative department at the beginning of the year.
The three are among 12 senior British advertising executives who will help to sift through the entries for the 52nd festival, which will run for six days from 19 June.
The other UK jurors are Marc Mendoza, the chief executive of Media Planning Group (Media Lions); Mitch Levy, the executive creative director of Joshua, and Colin Nimick, the creative director of OgilvyOne (Lions Direct at Cannes); Danny Kellard, the international creative director of Publicis Dialog, and Steve Aldridge, the Partners Andrews Aldridge creative partner (Lions Direct at Home); and Chis Aldous, the creative director at Publicis (Integrated).
Malcolm Poynton, Ogilvy & Mather's executive creative director, will be the president of the Radio Lions jury, where he is joined by Tony Hertz, the creative and managing director of Hertz Radio & Other Clever Advertising.
The TBWA\Worldwide creative director, John Hunt, will lead the film jury.
Terry Savage, the festival's chief executive, said: "We have some great creative talent and personalities representing the UK this year. Between them, they have won 16 Lions."
Up to 8,000 industry figures from 75 countries are expected to attend this year's event.