Count Philip of Nassau-Idstein (1450 – 16 June 1509) was the youngest son of Count John II of Nassau-Wiesbaden-Idstein and his wife, Mary of Nassau-Siegen.
In 1470, he married Margaret (1456–1527), the daughter of Count Palatine Louis I "the Black" of Zweibrücken-Veldenz.
After John II died in 1480, Philip ruled Nassau-Idstein, while his elder brother Adolf III ruled Nassau-Wiesbaden.
His brother Adolf III inherited Nassau-Idstein, thereby reuniting Nassau-Wiesbaden-Idstein.
This article about a member of the German nobility is a stub.