Princess Magdalena Augusta of Anhalt-Zerbst (13 October 1679 – 11 October 1740) was, by birth, a Princess of Anhalt-Zerbst and, by marriage, a Duchess of Saxe-Gotha-Altenburg.
She was the maternal grandmother of George III of the United Kingdom.
She was born Princess Magdalena Augusta of Anhalt-Zerbst.
Her father was Karl of Anhalt-Zerbst and her mother was Duchess Sophia of Saxe-Weissenfels.