On August 18, 2021 Princess Marie suffered a stroke and was hospitalized on the same day. Three days later, she passed away at a hospital in Grabs, Switzerland at the age of 81. Her family was with her during her stay at the hospital. Princess Marie was the wife of the reigning Prince of Liechtenstein, Hans-Adam II. Their son, Alois, Hereditary Prince of Liechtenstein, has been regent of Liechtenstein since 2004.