Tolui, Tolui Khan (meaning the Khan Tolui)) (1192–1232) is the youngest son of Genghis Khan by his chief khatun Börte.

His ulus, or territorial inheritance, at his father's death in 1227 is the homelands in Mongolia, and it is he who serves as civil administrator in the time it takes to confirm Ögedei as second Great Khan of the Mongol Empire (1206–1368).

Before that, he had served with distinction in the campaigns against the Jin Dynasty, the Xi Xia and the Khwarezmid Empire, where he was instrumental in the capture and massacre at Merv and Nishapur.

He is a direct ancestor of most of the Emperors of Mongolia and the Ilkhanids.

Tolui never uses the title of Khagan himself; though neither Genghis Khan nor his immediate three successors ever use any reigning titles, unlike the neighboring Chinese dynasties in the south.

Tolui is awarded the title of Khagan by his son Möngke and is given a temple name (Chinese: Yuán Ruìzōng) by his other son Kublai, when he establishes the Yuan Dynasty a few decades later.