Ahmad Sanjar (, Persian: احمد سنجر; full name: Muizz ad-Dunya wa ad-Din Adud ad-Dawlah Abul-Harith Ahmad Sanjar ibn Malik-Shah) (b. 1085 – d. 8 May 1157) was the Seljuq ruler of Khorasan from 1097 until in 1118 when he became the Sultan of the Seljuq Empire, which he ruled as until his death in 1153. Bosworth notes Sanjar is a Turkic name, denoting "he who pierces", "thrusts".