Anna Maria von Eggenberg, née Brandenburg-Bayreuth

Anna Maria Princess of Eggenberg, née Brandenburg-Bayreuth (born 30 December 1609 in Bayreuth; died 8 May 1680 in Ödenburg) was a Margravine of Brandenburg-Bayreuth and, by marriage Johann Anton I von Eggenberg, a Fürstin (princess) of Eggenberg.

She was married according to the Roman Catholic rite into the Styrian noble family of Eggenberg on 23 October 1639 in Regensburg to Prince Johann Anton I. von Eggenberg, Duke of Krumau, who subsequently received the opportunity to acquire the shire of Gorizia and Gradisca along the Adriatic coast two years later from his boyhood friend, Emperor Ferdinand III. The marriage ceremony had been negotiated by Christian Wilhelm von Brandenburg and prince Johann Anton I thereby secured for himself Brandenburg support for his claim to a seat in the Imperial Diet. She demonstrated a strong character and conviction by holding on firmly to her family's Protestant faith in spite of her marriage to the son of Hans Ulrich von Eggenberg, chief minister of Emperor Ferdinand II, who had prosecuted the Counter-Reformation in the Habsburg hereditary lands as well as the Thirty Years' War.