Abstract: In the modern time，western thoughts of democracy and constitution have spread in China.Influenced by these thoughts，Chinese people gradually became politically conscious and valued western democratic system.The legality of autocratic monarchy which had existed in China for more than two thousand years is fundamentally doubted，shaken and denied.So，the legality of the reign of Qing Empire has encountered unprecedented crisis.Qing Dynasty carried out a series of political reforms to save its reign.However，on the contrary，the reforms triggered more complex social contradictions and conflicts.Inevitably，Qing Dynasty could not get away from the fate of fall.

Key words: autocratic monarchy, Qing Dynasty, condition of the people, political system, political decay