Ms Markle's mother, Doria Ragland, will meet the Queen for the first time at Windsor Castle later, accompanied by her daughter and future son-in-law.
Ms Ragland has already been introduced to some of the Windsors - including Prince Charles and Prince William.
It remains unclear who will walk Ms Markle down the aisle of St George's Chapel as her father will not attend.
Ms Markle released a statement on Thursday confirming her father would not attend the wedding and saying she hoped he could be given space to focus on his health.
