In Ancient China, the military troops and military command were the footstones of a ruling system. Rational allocation and control of military power were the key elements of a political power. Although the military command system in the Wei and the Jin Dynasties were almost the same, the courses of rise and fall of the two political powers were different, because the two dynasties adopted different ways of allocation and control of military power; (2) In the Wei Dynasty, the local military command was vested in Dudu , the military governor of province. An independent office called Jun Si ( Jun means military, and Si , to take charge of ) was set to take charge of supervising the military affairs. A levied army stationing at the capital called Zhong Jun ( Zhong means central or imperial, and Jun the troop or the army), or Zhong Ling Jun ( here Ling means to lead or to command ) serving as a threatening equilibrium and ensuring the stability of the state of government; (3) While in the Jin Dynasty, the facts that the royal princes came in Dudu's stead, and the troops stationed in Zhou ( the name in ancient China meant the administrative district consisting of several countries) were disbanded, the areas under military command were becoming the manor estates of the royal princes, and, besides, the numbers of Zhong Jun were reduced meant that the rule of the Jin Dynasty was short lived.