Stephen of Simmern-Zweibrücken was Count Palatine of Simmern and Zweibrücken from 1410 until his death in 1459.

The Duchy of Palatinate-Zweibrücken was a duchy of the Holy Roman Empire with full voting rights to the Reichstag. Its capital was Zweibrücken. The reigning house, a branch of the Wittelsbach dynasty, was also the Royal House of Sweden from 1654 to 1720.