The princess, 32, will marry Paris-based businessman Nicolas Bagory in a civil ceremony on Saturday 22 April at the City of Luxembourg Town Hall.
After the ceremony, a reception will take place at the Grand Ducal Palace with the bride and groom's families and guests in attendance.
The couple's religious wedding will take place on 29 April at Saint Trophyme church in Bormes-Les-Mimosas, France.
Princess Alexandra, seventh in line to the Luxembourg throne, is an active working member of the royal family and a professional linguist. Her fiancé Nicolas grew up in Brittany, going on to study political science and classics. He now works on the creation of social and cultural projects.
Grand Duke Henri and Grand Duchess Maria Teresa are parents to Hereditary Grand Duke Guillaume, 41, Prince Félix, 38, Prince Louis, 36, Princess Alexandra and Prince Sébastien, 31.
Prince Guillaume and Princess Stephanie welcomed their second son, Prince François, on 27 March. They are also parents to Prince Charles, who turns three next month. See what Prince Guillaume had to say about his newborn son in the clip below...
Meanwhile, Prince Félix has two children with his wife, Princess Claire – Princess Amalia, eight, and Prince Liam, six.
Prince Louis shares two sons with his former wife, Tessy Antony de Nassau – Prince Gabriel, 17, and Prince Noah, 15.
Louis and Parisian lawyer Scarlett-Lauren Sirgue called off their engagement last February.
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