This article argues that the Karma Kagyu sect of Tibetan Buddhism, which was popular in the area from Xining to Anding-Wei and Hami in the mid-Ming dynasty, made an important impact on the selection of the successors to the King Zhongshun of Hami. The Ming court also took advantage of the Karma Kagyu sect to unite all the Jimi-Wei Station to the west of the Jiayuguan Pass. The artistic style of the bronze Buddhist statues preserved at the Hami Museum suggests that the gilt-bronze Green Tara statue was cast between the mid-17th century and the early 18th century. The bronze statue of the White Tara was dated to around the 15th century. The statues show that Tibetan Buddhism existed in Hami in the Ming dynasty. Using the early legend of the Hui royal family in Hami in the Qing dynasty, this article points out that the Naqshbandi sect from the Khan ate of Bukhara defeated the Karma Kagyu sect in 1605 to 1606. The Uygur ( Weiwuer) and the Mongols in Hami converted to Islam and became the closer ethnic origin of today's Uyghurs in Hami. Hami is not only on the east-west tributary trade route but also in the transitional zone between the northern Mongolian steppe and the Qinghai-Tibet Plateau. The society of Hami thus has the social and cultural characteristics of the north-south geographical corridor and is an important relay point for the spread of Tibetan Buddhism. Positioning Hami in the frame of the history of Mongolian-Tibetan-Han ethnic relations and the history of MongolianTibetan-Han Buddhism, this article reveals how Tibetan Buddhism became a source of social resistance when Islam's armed missionary was marching east.