Mulay, Mûlay, Bulay (Mongolian: Мулай or Molay for the Franks, fl. 1289 - 1312) was a general under the Mongol Ilkhanate ruler Ghazan at the end of the 13th century. Mulay was part of the 1299–1300 Mongol offensive in Syria and Palestine, and remained with a small force to occupy the land after the departure of Ghazan. He also participated in the last Mongol offensive in the Levant in 1303. His name has caused confusion for some historians, because of its similarity with that of the contemporary Grand Master of the Knights Templar, Jacques de Molay.

According to Maitland Muller's translation of Jami' al-Tawarikh, he was a member of Küin clan of Tatar tribe. Michael Hope calls him a maternal uncle to Ghazan various times, while Rashid al-Din doesn't specify him as brother to Ghazan's mother Qultaq, but rather as a brother to certain Küräk Temür, whom Arghun took Qultaq from:

Arghun Khan requested Ghazan's mother, Qultaq, the daughter of Kihtar Bitigchi of the Dörbän tribe, at the age of twelve from Küräk Temür, the brother of Uruqtu and Mulai.

— Rashid al-Din Hamadani, Jami' al-tawarikh, Volume 3

In any case, he was close to Ghazan, by the virtue of his fiefs were located in Quhistan, which was located in Ghazan's viceroyalty of Khorasan. He was on side of Ghazan when Nawruz revolted in 1289. He captured Nawruz's puppet prince Hulachu on 30 April 1289 on behalf of Ghazan. He spent summer of 1290 repulsing attacks by Qaraunas under Danishmend Bahadur. Facing failure, he went back to Quhistan to reinforcements in 1291. Hearing death of Arghun in March, he rejoined Ghazan near Simnan, where he was given a sister of emir Satalmish, another emir under Ghazan. He was sent with Sutai against rebellious malik of Zozan and Mihrabanid prince Shah Ali who came to his aid in 1292. Siege was quick, Shah Ali was defeated and fled to Sistan with a thousand men.

After Ghazan's accession, he became member of kheshig and was sent to Khorasan to arrest Tughan, who was also from Quhistan. Later, he joined Nawruz in 1295 against Duwa. However, Ilkhanid prince Sogai (son of Yoshmut) refused to join campaign in Khorasan, believing this was Nawruz's plot further deprive nobility of their possessions. Nawruz informed Ghazan of this plot, subsequently executed him. It was Mulay who brought news to Ghazan in Arran. Emir Taghachar was also executed for involving in a conspiracy with Sogai and was replaced by Mulai in Diyar Bakr.

His appointment in Mamluk border was not without incidents. In 1299, Ghazan marched with his generals Mulay and Samagar towards Egyptian Mamluk-controlled Syria. The Mongols successfully took the city of Aleppo, and then defeated the Mamluks in the Battle of Wadi al-Khazandar, on December 23 or 24, 1299. At some point, Ghazan ordered Mulay to lead a raid through Palestine, with a tumen, a force of 10,000–20,000 horsemen. Mulay's group split off from Ghazan's army, and pursued the retreating Mamluk troops as far as Gaza, pushing them back to Egypt. The bulk of Ghazan's forces then proceeded on to Damascus, which surrendered at some point between December 30, 1299, and January 6, 1300, though its Citadel resisted. Ghazan then retreated with most of his forces in February, probably because the Mongol horses needed fodder. He promised to return in November to attack Egypt. Mulay and his horsemen returned to Damascus around March 1300, and followed Ghazan back across the Euphrates. In May 1300, the Egyptian Mamluks returned from Egypt and reclaimed the entire area without a battle.

In 1303, the Mongols, led by Ghazan's generals Mulay and Qutlugh-Shah, reappeared in great strength in Syria (about 80,000) together with the Armenians. However, they were defeated at Homs on March 30, 1303, and also at the decisive Battle of Shaqhab, south of Damascus, on April 21, 1303. It is considered to be the last major Mongol invasion of Syria. Mulai was bastinadoed for his incompetence during the battles on the orders of Ghazan on 17 July 1303.