Tokhtamysh (died 1406) was the prominent khan of the Blue Horde, who briefly unified the White Horde and Blue Horde subdivisions of the Golden Horde into a single state. He was a descendant of Genghis Khan's eldest grandson, Orda Khan or his brother Tuqa-Timur.

Tokhtamysh appears in history in 1376, trying to overthrow his uncle Urus Khan, ruler of the White Horde, and fleeing to the great Timur. Tokhtamysh outlived Urus and both his sons and forcefully ascended the throne of the White Horde in 1378 with Timur's backing.

Tokhtamysh dreamed of emulating his ancestors and made plans to reunite the Ulus Jochi. In 1380, he invaded the Blue Horde by fording across the Volga. The ruler of the Blue Horde, Mamai, was killed shortly after the Battle of Kulikovo, making Tokhtamysh's victory over the horde all the easier.

Having divided the Blue and White Hordes into the Golden Horde in 1382 Tokhtamysh led a successful campaign against Russia as a punishment for the Kulikovo defeat - setting back, though not ending, the Russian aspiration to free themselves of Mongol rule. In just six years, Tokhtamysh had reunified the Mongol lands from Crimea to Lake Balkhash.