Prince Charles will walk Meghan Markle down the aisle when she marries his son Prince Harry on Saturday.
Ms Markle's own father, Thomas Markle, this week confirmed he would not attend the ceremony due to his ill health.
In a statement, Kensington Palace said Ms Markle had asked Prince Charles, the heir to the throne, to accompany her down the aisle of the Quire of St George's Chapel on her wedding day.
The statement implied that Ms Markle would still enter the chapel alone with her bridesmaids and page boys, as the Quire is located about half-way down the church.
"The Prince of Wales is pleased to be able to welcome Ms Markle to The Royal Family in this way," the statement said.
The announcement came as Buckingham Palace confirmed the Queen's husband Prince Philip would also be attending the ceremony.
The 96-year-old had successful hip replacement surgery last month and retired last year from public appearances.
Ms Markle yesterday confirmed her father would not attend her wedding in order to focus on his health.
"Sadly, my father will not be attending our wedding," Ms Markle said in the statement.
"I have always cared for my father and hope he can be given the space he needs to focus on his health.
"I would like to thank everyone who has offered generous messages of support.
"Please know how much Harry and I look forward to sharing our special day with you on Saturday."
Mr Markle announced this week that he would not be attending his daughter's wedding to avoid embarrassing her and the Royal family.
The decision came after he staged a series of photos of himself preparing for the event with a paparazzi agency.
The 73-year-old also said he had suffered a heart attack last week and underwent surgery on Wednesday.
Ms Markle's mother, yoga instructor Doria Ragland, was due to take tea with Queen Elizabeth, Harry's grandmother, on the eve of the wedding.
A source close to the royal family said Ms Ragland charmed her daughter's future father-in-law when they met on Wednesday.
Millions of people are expected to tune in worldwide when Prince Harry and Meghan Markle wed at 11:00am on Saturday (local time).
Police are expecting more than 100,000 people to throng the streets outside Windsor Castle, the Queen's home west of London and the oldest and largest inhabited fortress in the world.
Harry, 33, a former army officer and one-time royal wild child, met his bride-to-be on a blind date in July 2016 after being set up through a mutual friend.
Ms Markle, 36, said she knew little about her royal date while Harry said he had never heard of Ms Markle or watched her TV series Suits.
However, it was love at first sight, and after just two dates, he whisked her off to Botswana for a holiday, camping under the stars.
The union between the Prince and a biracial American actress divorcee has drawn comparisons with remarkable episodes of recent royal history.
Edward VIII's relationship with American divorcee Wallis Simpson led him to abdicate in 1936.
The Queen's late sister Margaret also called off her marriage to an equerry (officer of the Royal household) Peter Townsend, whose ex-wife was still alive during his romance with the Princess.