Öljaitü (Öljaitü Qaghan, اولجایتو), also known as Mohammad-e Khodabande (محمد خدابنده, khodābande from Persian meaning the "slave of God" or "servant of God"; 24 March 1282 – 16 December 1316), was the eighth Ilkhanid dynasty ruler from 1304 to 1316 in Tabriz, Iran. His name means "blessed" in the Mongolian language.
He was the son of the Ilkhan ruler Arghun, brother and successor of Mahmud Ghazan (5th successor of Genghis Khan), and great-grandson of the Ilkhanate founder Hulagu.
Öljaitü was born as the son of Arghun and his third wife, Keraite Christian Uruk Khatun on 24 March 1282 during his father's viceroyalty in Khorasan. He was given the name Khar-banda (Mule driver) at birth, raised as Buddhist and later baptised in 1291, receiving the name Nikolya (Nicholas) after Pope Nicholas IV. However, according Tarikh-i Uljaytu (History of Oljeitu), Öljeitu was at first known as "Öljei Buqa", and then "Temüder", and finally "Kharbanda". Various c. Same source also mentions that it rained when he was born, and the delighted Mongols called him by the Mongolian name Öljeitu (Өлзийт), meaning auspicious. He was later converted to Sunni Islam along with his brother Ghazan. Like his brother, he changed his first name to the Islamic name Muhammad.
He participated in battles involving Ghazan's fight against Baydu. After his brother Ghazan's accession to throne, he was appointed as viceroy of Khorasan. Despite being appointed heir of Ghazan since 1299, after hearing news of his death he sought to eliminate potential rivals to throne. First such act was taken against Prince Alafrang, son of Gaykhatu. He was killed by an emissary of Öljaitü on 30 May 1304. Another powerful emir, Horqudaq was likewise captured and executed.
He arrived in the Ujan plain on 9 July 1304 and was crowned on 19 July 1304. Rashid al-Din wrote that he adopted the name Oljeitu following Yuan emperor Öljeitu Temür enthroned in Dadu. His full regnal title was Ghiyath al-Din Muhammad Khudabanda Öljaitü Sultan.