The actress joined her fiancé, Prince Harry, at the annual event, along with over 50 members of the royal family. All of the Queen's children were in attendance, along with most of her grandchildren.
Royal guests included Prince William, Kate Middleton and their children, Prince George and Princess Charlotte, as well as Prince Charles, Camilla, Duchess of Cornwall, Princess Eugenie and Princess Beatrice. Harry and Markle arrived from Kensington Palace shortly after William and Middleton.
Markle has previously met the Queen multiple times, although this is believed to be the first time she has had lunch with the entire royal family at the palace. Last week, she attended the Queen's private party for staffers at Windsor Castle, charming guest after guest.
"It was a good opportunity for her to get to know the close part of the family as it were," a family friend said of the occasion.
The 36-year-old will also join the family at the Queen's Sandringham estate on Christmas Day, making her the first royal fiancée to spend Christmas with the family.
Photo Credit: Getty / Samir Hussein