Born in Vienna, as a sixth child to Maximilian Karl Albert, Prince of Löwenstein-Wertheim-Rochefort and his wife, Countess Maria Polyxena Khuen of Lichtenberg and Belasi (1658-1712).
Her father had entered imperial service at a young age, was an imperial counselor from 1684 thus her birth in Vienna, the capital of the Holy Roman Empire then ruled by Leopold I.
Her mother was a member of the family who ruled the County of Lichtenberg und Belasi.
She herself would marry her first cousin; Eleonore's paternal aunt Princess Maria Anna of Löwenstein-Wertheim-Rochefort had married William, Landgrave of Hesse-Rheinfels-Rotenburg, father of her husband Ernest Leopold of Hesse-Rotenburg, William's son and heir.
Her eldest granddaughter, Princess Eleonora of Savoy, was named after her.