Qutb-ud-din Aybak was a ruler of Medieval India, the first Sultan of Delhi and founder of the Slave dynasty (also known as the Mamluk dynasty). He served as sultan for only four years, 1206-1210.

Qutb-ud-din was a Turk of the Aybak tribe, and was born in Central Asia. As a child he was captured and sold as a slave (mamluk). He was purchased by the chief Qazi of Nishapur, who treated him like one of his own sons. Aibak received good education and was trained in archery and horsemanship. When his master died, his master's sons, who were jealous of Aibak, sold him to a slave merchant. Qutb-ud-din was a bought by Sultan Muhammad Ghori, who, from the Ghor region of central Afghanistan, had conquered present-day Afghanistan, Pakistan, Turkestan, and northern India by his death in 1206. Qutb-ud-din rose through the ranks to become Muhammad's most trusted general, and was increasingly left in charge of Muhammad's Indian campaigns and the administration of his Indian possessions as Muhammad's attention turned to affairs in Central Asia after 1192. Qutb-ud-din's greatest military successes occurred while still a subordinate. He was responsible for most of Muhammad's conquests in northern India, and was appointed as Muhammad's viceroy in India. Muhammad had no male heirs, and upon his death in 1206 Qutb-ud-din, after a brief power struggle, succeeded in establishing himself as Sultan of Muhammad's empire in Afghanistan, Pakistan, and northern India; Muhammad's Central Asian posessions had been captured by the Mongol leader Ghengis Khan.

Though his tenure as a ruler was only four years, and most of them were spend in dealing with the revolts of nobles like Taj-ud-din Ildiz, Nasir-ud-din Qubachah and a few Hindu chiefs, yet he established a firm administrative system. He restored peace and prosperity in the area under him and roads were free from thieves and robbers. Aibak was known as Lakh Baksh because of his generosity. He was also a pious Muslim. Historians have praised his evenhanded justice. He patronized Nizami and Fakh-i-Mudabbir, both of whom dedicated their works to Aibak.

Qutb-ud-din moved the capital of the empire from Ghazni to Lahore, and later moved the capital to Delhi, and thus is considered as the first Muslim ruler of South Asia. He started construction of the city's earliest Muslim monuments, the Quwaat-al-Islam Mosque and the Qutb Minar, which was completed by his successor Iltutmish.

Qutb-ud-din died accidentally in 1210; while playing a game of polo, his horse fell, and he was impaled on the pommel of his saddle. He is buried near the Anarkali Bazaar in Lahore. His tomb was destroyed by the Mongol attack on Lahore in 1241, and a new tomb was constructed over his grave around 1970. He was succeeded as Sultan by Shams-ud-din Iltutmish, another ex-slave of Turkic ancestry, who married Qutb-ud-din's daughter.