Accompanied by Prince Charles, the royal revealed that her family had voted for the actress and her dance partner Giovanni Pernice on the BBC One show – something that has gone down in Strictly history.
WATCH: Prince Charles and Camilla visit EastEnders set and call Ross Ayling-Ellis a 'star'
The royal couple were guided around Albert Square on the Elstree set and watched as the cast filmed special scenes that feature the residents celebrating the Queen's Platinum Jubilee at a street party.
Camilla revealed that she had voted for Rose in Strictly
Deaf actress Rose, who plays Frankie Lewis in the show, presented Camilla with a bouquet of flowers, adding that it was an "honour" to meet the Duchess.
Camilla, who was wearing a silk dress and cream coat by Anna Valentine, said: "Rose, the Strictly star. I said we were all voting for Rose, I don't know how you did all those dances."
The royals posed for a group photo on set
The champion then asked if the Queen watched Strictly, to which Camilla replied: "I think she does. She probably watched you. You have to find out."
After they exchanged words, Rose told the PA news agency: "It was really funny because she's a huge fan of Strictly Come Dancing and she mentioned that she voted for me which is so lovely, and her grandchildren watch it.
"It is amazing, so lovely. I mean come on, it's the royal family voting for me, sometimes you forget how many people watch the show, I am mind-blown."
The episode depicted a Platinum Jubilee street party
The royal couple were shown around the new set of EastEnders, which was originally due to be finished in 2018. A special moment came during a group photograph of the cast and crew alongside the royals.
Charles and Camilla also met other cast members including Steve McFadden, who plays Phil Mitchell, Rudolph Walker (Patrick Trueman), Danny Dyer (Mick Carter), Tameka Empson (Kim Fox), Natalie Cassidy (Sonia Fowler) and Gillian Taylforth (Kathy Beale) to name just a few as well as Walford's own 'Princess' Letitia Dean (Sharon Watts).
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