About political crisis, in our country the politicians and scholars always treat it as constitutional crisis and presume that the operation of power will be fine as long as the system design is also fine. This article is to analysis the power succession process from the end of the Ching Dynasty to the beginning of the Republic and to point out that it is not the system design but the power players who should believe in the mechanism of the political system. In other words, the stability to uphold a political regime is from legitimacy not legality. All political administrators like to form a cultural hegemony and make their subordinates and followers believe in their ruling legitimacy, but the ruling legitimacy just can not be created by the rulers single handed. The power holder must be able to response to the concerns of the social majority and address the issues of the age, then find the convincing legitimacy. The north and south government in the early Republic did not grasp the importance of ruling legitimacy and then caused the instability of executive power.