Around 350 privileged guests are expected to witness the young royals say 'I do'.
After exchanging their vows, the newlyweds will make their way to the town's magnificent 14th century Royal Covent where celebrations will unfold to mark the new union.
The pair chose to hold the religious ceremony in the medieval town because the surrounding area holds many special memories for them.
"We both like to remember the wonderful summer holidays, which we spent in the south of France at the house of my parents near Lorgues or with my future parents-in-law in Cabasson, just the two of us or with our families and friends," PhD student Claire said ahead of the nuptials.
"The idea to get married in the Provence came up all by itself, because we wanted to extend these precious moments with our loved ones."
After the wedding celebrations 29-year-old Felix plans to whisk his new wife off to a secret destination.
"The day after our wedding we will depart on our honeymoon, and I will personally take care of the organisation," he told Luxembourgish newspaper wort.lu in a joint interview with his future wife ahead of the big day.
"It is tradition in our family that the destination of the honeymoon is a surprise for the bride, that is only revealed at the last minute before departure..."
Once they return from their honeymoon, they won't be far from the joyful memories of their special day in Saint-Maximin.
Princess Claire explained her and her husband's future plans.
"We decided to begin our life as newlyweds in the south of France, where we will manage a family winery."