Nasir al-Din Mahmud I (1088–1094) was an infant sultan of the Seljuk Empire from 1092 to 1094,[1] with most power held by his mother Terken Khatun.

After Mahmud's forces lost a battle at Borujerd, he and his mother were assassinated by the family of the former vizir Nizam al-Mulk.

[3][4] Eventually, however, the caliph al-Muqtadi agreed to let her govern if the khutba was said in the name of her son, and if she did so assisted by a vizier he appointed for her, a condition to which she saw herself forced to accept.

[5] She was thus not formally a regent, but she secured the reins of power de facto with al-Shirazi as vizier and Unar as army commander.

[7] In Anatolia, Malik Shah I was succeeded by Kilij Arslan I, who escaped from Isfahan; and in Syria by Mahmud's uncle Tutush I.