Margherita de' Medici (31 May 1612 – 6 February 1679) was Duchess of Parma and Piacenza by her marriage to Odoardo Farnese, Duke of Parma. Margherita was regent of Piacenza in 1635 and regent of the entire duchy in 1646 after the death of her husband.

She was the fourth of eight children and the second daughter born to Cosimo II de' Medici, Grand Duke of Tuscany and his wife Maria Magdalena of Austria.

Margherita's siblings included: Ferdinando II de' Medici, Grand Duke of Tuscany, Cardinal Gian Carlo de' Medici, Cardinal Leopoldo de' Medici and Anna, wife of Ferdinand Charles, Archduke of Further Austria. Margherita's other siblings died in childhood or early adulthood.

Her paternal grandparents were Ferdinando I de' Medici, Grand Duke of Tuscany and his wife Christina of Lorraine. Ferdinando was a son of Cosimo I de' Medici, Grand Duke of Tuscany and his first wife Eleanor of Toledo. Margherita's maternal grandparents were Charles II, Archduke of Austria and his wife Maria Anna of Bavaria. Maria Anna was the eldest daughter of Albert V, Duke of Bavaria and his wife Archduchess Anna of Austria. Anna was a daughter of Ferdinand I, Holy Roman Emperor and his wife Anna of Bohemia and Hungary. Hence Margherita is a descendent of the Holy Roman Emperors.

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