Countess Joanne of Nassau-Siegen[note 1] (1444 – May 1468), German: Joanne Gräfin von Nassau-Siegen, official titles: Gräfin zu Nassau, Vianden und Diez, Frau zu Breda, was a countess from the House of Nassau-Siegen, a cadet branch of the Ottonian Line of the House of Nassau, and through marriage Countess of Waldeck.

Joanne was born in 1444[1][2] as the second daughter of Count John IV of Nassau-Siegen[1][2][3] and his wife Lady Mary of Looz-Heinsberg.

[1][2][note 2] Joanne married on 14 October 1464[1][2][3] to Count Philip I of Waldeck (1445 – 1475), the eldest son of Count Wolrad I of Waldeck and Countess Barbara of Wertheim.

[1][2][4] The parents on both sides are said to have designated their children for each other as early as 1452.

[1][2] From the marriage of Joanne and Philip only one son was born:[3]