Almas Beg (died c. 1301-1302), better known by his title Ulugh Khan, was a brother and a general of the Delhi Sultanate ruler Alauddin Khalji. He held the iqta' of Bayana in present-day India.
Ulugh Khan played an important role in Alauddin's ascension to the throne of Delhi in 1296. He lured the former Sultan Jalaluddin to Kara, where Alauddin assassinated Jalaluddin. He successfully besieged Multan, and subjugated the surviving members of Jalaluddin's family.
In 1298, Ulugh Khan repulsed a Mongol invasion from the Chagatai Khanate, which greatly increased Alauddin's prestige. The next year, he and Nusrat Khan raided the wealthy province of Gujarat, obtaining a huge amount of wealth for Alauddin's treasury. He led the reinforcement unit in the Battle of Kili (1299) against the Mongols, and held command in the initial phases of the Siege of Ranthambore (1301). He died a few months after the Ranthambore campaign ended, although a fictional account in Amir Khusrau's Ashiqa suggests that he led Alauddin's forces in the later years.
Ulugh Khan was originally known as Almas Beg. His father Shihabuddin Mas'ud was the elder brother of the Khalji dynasty's founder Sultan Jalaluddin. Besides his elder brother Alauddin (originally known as Ali Gurshasp), he had two other brothers Qutlugh Tigin and Muhammad.
Both Alauddin and Ulugh Khan married Jalaluddin's daughters. After Jalaluddin became the Sultan of Delhi, Alauddin was appointed as Amir-i-Tuzuk (equivalent to Master of ceremonies), while Almas Beg was given the post of Akhur-beg (equivalent to Master of the Horse).