Abstract Kushan Empire might be tracted back to Kushan Yabgus in Bactria territory, it was called Yuezhi in "Late Han Book". Tochari was another name of Bactria arsa in "New Targ Book", whore ruled by the tribes altervately. By way of the analysis on the changes of the native Yabgus establishment and its original language, it was testified that the founding of Kush Yabgus by Yuezhi with the purpose of controlling the area. At that time, most part of the land was within the territory where lived by ludo-European Tribes, and the language of Yabgus was also a branch of theirs. In accordance with the ruler Yuezhi enforcement to Boctria area, not orly its Kushan Yabgus became a part as Kushan Empire of Yuezhi, but also once its capital Lanshi city was managed by Yuezhi as the first city. Henceforth the Yuezhi's nomadic life was changed into as farmer's in the fired place too. From all those above, it is exposed that the relation between Kushan Empire and Bactria area was closely connected. This text consists of four chapters as below : 一、Foreword 二、Yabgus and its establishments in Tradition. 1. Yabgus of the kingdoms in the West Land of Han Dynasty. 2. The origin of the language of Yabgus. 3. The establishments of Yabgus in tradition. 三、The founding and changings of Kushan Yabgus. 1. Bactria kingdom during the period of Kushan Yabgus. 2. The relative among Yuezhi and five Yabgus. 3. The influences of Lanshi city to Kushan Empire in politics and community. 四、Conclusion
如有問題歡迎與系統管理員聯繫 
