The father of groom Prince Harry stepped in after Markle's dad fell ill days before the wedding and was unable to fly to Britain.
Markle appealed for people to give Thomas Markle "the space he needs to focus on his health" amid reports he had undergone a heart procedure.
The palace said Friday that Markle's future father-in-law, the heir to the British throne, would walk Markle down the aisle at St. George's Chapel in Windsor on Saturday. The palace says he "is pleased to be able to welcome Ms. Markle to the Royal Family in this way."
The Prince of Wales is pleased to be able to welcome Ms. Markle to The Royal Family in this way.— Clarence House (@ClarenceHouse) May 18, 2018
Prince Philip, 96, also plans to be in attendance at the wedding, despite concerns about his health and retiring from public service last year.
As for the night before the nuptials, Markle will stay at a hotel with her mother and Prince Harry will be at a separate hotel with his brother, Prince William.
Markle's mother, Doria Ragland, will meet Queen Elizabeth II on Friday.
The Associated Press contributed to this report.