Abu Sa'id Taj ad-Dawla Tutush I (Turkish: I. Tutuş, Arabic: أبو سعيد تاج الدولة تتش السلجوقي) (died 1095) was the Seljuq ruler (probably sultan or emir) of Damascus from 1079 to 1095, succeeding Atsiz ibn Uvaq al-Khwarazmi. He finished the construction of the Citadel of Damascus, a project that had begun under the direction of Atsiz. Tutush took control of Syria in 1085 from his brother, the sultan of the Great Seljuq Empire Malik Shah I, but lost it in 1086, only to recapture it in 1094. Tutush, along with his general the Kakuyid Ali ibn Faramurz, were shortly defeated in a battle near Ray in 1095, where he and Ali were killed. Tutush's younger son Duqaq then inherited Damascus, causing Duqaq's older brother Radwan to revolt, splitting their father's realm.