Anna Maria Franziska of Saxe-Lauenburg (13 June 1672 – 15 October 1741) was the legal Duchess of Saxe-Lauenburg in the eyes of the Holy Roman Emperor, the overlord of Saxe-Lauenburg, from 1689 until 1728; however, because her distant cousin George William, Duke of Brunswick-Lüneburg, conquered the duchy by force in 1689, she exercised no control over the territory, instead living in her manors in Bohemia.

She was Grand Duchess of Tuscany as the wife of the last Medici Grand Duke, Gian Gastone.

Anna Maria Franziska was the elder surviving daughter of Julius Franz, Duke of Saxe-Lauenburg, and Maria Hedwig of the Palatinate-Sulzbach. She married Philipp Wilhelm August of the Palatinate in 1690, with whom she had her only child, Maria Anna, in 1691. She was widowed in 1693. Four years later, she married Gian Gastone de' Medici, a Prince of Tuscany. With her brother-in-law Ferdinando de' Medici's death in 1713, her husband became Tuscany's heir-apparent. She became Grand Duchess of Tuscany upon the incumbent ruler's death in 1723. She was Grand Duchess for fourteen years before being widowed again in 1737.

Anna Maria Franziska was born on 13 June 1673. She was the second child of the reigning duke of Saxe-Lauenburg and Maria Hedwig of Sulzbach, who died when Anna Maria was nine years-old.

With the death of her father Duke Julius Francis on 30 September 1689 the Lauenburg line of the House of Ascania was extinct in the male line. However, female succession was possible by the Saxe-Lauenburgian laws. So the legal female heir to the throne, Duchess Anna Maria Franziska, and her sister Sibylle of Saxe-Lauenburg fought for the succession of the former, the elder of them. Also Julius Francis' cousin, Eleonore Charlotte of Saxe-Lauenburg-Franzhagen, claimed the succession. Their weakness was abused by Duke George William of the neighbouring Brunswick-Lunenburgian Principality of Lunenburg-Celle, who invaded Saxe-Lauenburg with his troops, thus inhibiting Anna Maria's ascension as Duchess regnant.

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