The Footballers' Wives actress and her professional partner were bottom of the judges' leaderboard after only scoring a combined total of 59 out of 100 for their Latin and ballroom dances.
Rouass's salsa came in for particular criticism from the panel, which included fifth judge Darcey Bussell for the first time, totalling only 26 points. Bruno Tonioli said that a "deflated balloon" would have had more rhythm than the actress.
Hollyoaks star Ricky Whittle and Natalie Lowe joined them in the bottom two, despite finishing top of the leaderboard with 95 out of 100. Head judge Len Goodman said that Whittle's foxtrot was "too marvellous for words".
After both couples performed in the dance-off, Craig Revel Horwood, Darcey Bussell and Alesha Dixon all voted to save Whittle and Lowe, sending Rouass out of the show.
Speaking afterwards, Rouass said: "Thank you, we have had such a ball. I would like to say it has been such a dream dancing with [Anton] for the last three months... it has been marvellous."
Du Beke added: "She has been a joy to work with - not once has she moaned or complained. She has been so much fun."
Chris Hollins and Ali Bastian will join Whittle in next Saturday's semi-final, which airs at 6.45pm on BBC One.