Count George of Nassau-Beilstein, later also Count of Nassau-Dillenburg, (1 September 1562 – 9 August 1623 in Dillenburg) was the third son of Count John VI "the Elder" of Nassau-Dillenburg (1536-1606) from his first marriage with Elisabeth of Leuchtenberg,In 1576, he studied at the University of Heidelberg. In 1578, he went to the Netherlands, to serve in the army, under Count of Günther XLI of Schwarzburg-Arnstadt.