| Philip, Count of Nassau-Idstein | |
| Noble Family: | House of Nassau |
| Father: | John II, Count of Nassau-Wiesbaden-Idstein |
| Mother: | Mary of Nassau-Siegen |
| Spouse: | Margaret of Zweibrücken-Veldenz |
| Birth Date: | 1450 |
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.
In 1509, Philip died childless. His brother Adolf III inherited Nassau-Idstein, thereby reuniting Nassau-Wiesbaden-Idstein.