Former Manchester United goalie Peter Schmeichel, comedian Jimmy Tarbuck and TV presenter Carol Smillie are also taking part.
Lytton, 17, who plays gangster's daughter Ruby Allen in the Walford-based soap, is the youngest contestant and will partner Italian ballroom dancer Vincent Simone.
King, who found fame as superbitch Kim Tate in Emmerdale, will team up with Love Island ladies' man Brendan Cole.
The other female celebrities are singer Mica Paris, comedy actress Jan Ravens and Casualty's Georgina Bouzova.
Joining Schmeichel and Tarbuck in the male line-up are former England rugby player Matt Dawson, newsreader Nicholas Owen, cricketer Mark Ramprakash, Coronation Street actor Ray Fearon, and Radio 1's DJ Spoony.
The BBC One show returns to Saturday nights next month with presenters Bruce Forsyth and Tess Daly.
Daly said: "With a line-up like this, the new series is set to be bigger and better than ever before. Where else could you see a Spice Girl dancing alongside Jimmy Tarbuck?"
In a change to last year's show, week one will see the boys dancing to stay in, while the girls entertain with a group mambo. The format will be reversed in week two.