Taj al-Din (died 1351) was the Mihrabanid king (malik) of Sistan from 1346 until 1350.
[1] In 1350 he was forced out of Shahr-i Sistan by a conspiracy, which proceeded to enthrone Jalal al-Din Mahmud in his place.
Fleeing first to Kerman, he made his way to Herat and convinced the Kartid malik Mu'izz al-Din Husayn to support his cause.
An army was assembled to restore Taj al-Din, but before it could march Herat was attacked by a coalition of tribes from the Chagatai Khanate under the command of the amir Qazaghan in 1351.
Taj al-Din fought in the Kartid army to defend Herat but was killed.