The display features personal belongings of the late Princess Grace, released by her children Prince Albert and Princesses Caroline and Stephanie.
Highlights include home videos made by the Philadelphia-born royal, who was taught to use a film camera by her friend, Alfred Hitchcock - the director behind some of the hit movies that helped elevate her to legendary status.
The fairytale wedding dress she wore for her 1956 wedding to Prince Rainier III is also on display, as well as several items of jewellery, paintings and intimate family photos.
Prince Albert was in town to open the show, which will run until February 28 next year.
It was originally created in 2007 to mark the 25th anniversary of the death of the princess, who died after sustaining injuries in a car accident with her daughter Stephanie.