HSH the Princess Caroline of Monaco, a.k.a. HRH the Princess of Hanover (born January 23, 1957), is the eldest daughter of Prince Rainier III of Monaco and his wife, Grace Patricia Kelly, a former American movie star. She is second in line to the Monegasque throne, after her brother, Prince Albert of Monaco, Marquis des Baux.

Her first husband was Philippe Junot (born 19 April 1940), a playboy banker. They were married 1978 and divorced in 1980. In 1992, the Roman Catholic Church annulled the marriage.

Her second husband was Stefano Casiraghi (1960-1990), an Italian industrialist who died in a boating accident. They were married on December 29, 1983, and had three children: Andrea Casiraghi|Andrea Albert Pierre (1984-), Charlotte Marie Pomeline Casiraghi (1986-), and Pierre Rainier Stefano (1987-). The two younger children are named for their maternal great-grandparents, Princess Charlotte of Monaco and Prince Pierre of Monaco.

Her third and present husband is Ernst August Albert Paul Otto Rupprecht Oskar Berthold Friedrich-Ferdinand Christian-Ludwig, Prince of Hanover, Duke of Brunswick and Lüneburg, Prince of Great Britain and Ireland (1954-). Prince Ernst August, head of the House of Hanover, is a German aristocrat who is the senior male descendant of King George III of the United Kingdom. They married in 1999 and have one child, Princess Alexandra Charlotte Ulrike Maryam Virginia of Hanover, who was born six months later. Subsequent to this marriage, Caroline adopted the style "Her Royal Highness, The Princess of Hanover, Duchess of Brunswick and Lüneburg, Royal Princess of Great Britain and Ireland, and by birth Princess of Monaco."

Princess Caroline had a liaison from 1990 until 1995 with French actor Vincent Lindon.