On 11 August 1955 she married Hugo Wessel (18 March 1930 – 22 February 2012), the son of Denise Orme and Theodore W."Tito" Wessel (a Danish millionaire and one-time Danish chargé d'affaires in Chile.)

On 21 September 1960, she married Frederik, Baron van Pallandt. They formed a singing duo, Nina & Frederik, and achieved worldwide popularity with their calypso-style songs. They had three children :

The couple parted in 1969 and divorced in 1975. In the early 1990s, Frederik van Pallandt settled in the Philippines where he and his Filipino girlfriend, Susannah, were shot dead in 1994.

Van Pallandt appeared with Richard Gere American Gigolo. She also appeared in several Robert Altman films during the 1970s, including The Long Goodbye, A Wedding, and Quintet. In 1969, she sang John Barry and Hal David's song "Do You Know How Christmas Trees Are Grown?" in the James Bond movie, On Her Majesty's Secret Service, starring George Lazenby. During 1969 and the early 1970s she appeared as a guest on several episodes of The Morecambe & Wise Show for BBC television, and in the later 1988 Tales of the Unexpected episode "A Time to Die".