Marie Antoinette was born at Großharthau, Kingdom of Saxony, the first child of Sizzo, Prince of Schwarzburg (1860–1926), and his wife, Princess Alexandra of Anhalt (1868–1958).

Her father was the son of Friedrich Günther, Prince of Schwarzburg-Rudolstadt, and Countess Helena von Reina (1835-1860); and her mother was the daughter of Frederick I, Duke of Anhalt, and Princess Antoinette of Saxe-Altenburg.

Through her mother she was descendant of King Frederick William II of Prussia.

Marie Antoinette married on 4 January 1925 in Wildenfels to Friedrich Magnus V, Count of Solms-Wildenfels (1886–1945), only son of Friedrich Magnus IV, Count of Solms-Wildenfels (1847-1910) and his wife, Anna Jacqueline, Countess of Bentinck-Aldenburg-Middachten (1855-1903).

[1] Following her brother's death in 1971, the House of Schwarzburg became extinct in the male line.