Prince Waldemar or Valdemar may refer to:
Anhalt-Köthen, a German principality Waldemar I, Prince of Anhalt-Zerbst (died 1368) Waldemar II, Prince of Anhalt-Zerbst (died 1371) Waldemar III, Prince of Anhalt-Zerbst (died 1391) Waldemar V, Prince of Anhalt-Köthen (died 1436) Waldemar VI, Prince of Anhalt-Köthen (1450–1508)
Other places Waldemar IV, Prince of Anhalt-Dessau (died after 22 July 1417) Prince Valdemar of Denmark (1858–1939) Prince Waldemar of Prussia (disambiguation), several people Woldemar, Prince of Lippe (1824–1895)