Giyasuddin Muhammad Uzbek Khan, better known as Uzbeg or Özbeg (1282–1341), was Khan of the Golden Horde from 1313 to 1341. He was the longest-reigning khan, under whose rule the state reached its zenith. He was succeeded by his son Tini Beg. He was the son of Toghrilcha and grandson of Mengu-Timur, who had been khan of the Golden Horde from 1266 to 1280.