In terms of endogenous institutional change, concepts such as "idea enlightenment," "red-line area" and "power structure" are more suitable to explain factors which generate the institution of the National People's Congress (NPC), the permanent system of the party congress, and the institution of the village committees in authoritarian China. The paper finds that Marxism-Leninism, Mao Zedong's thought and Deng Xiaoping's thought, respectively, influence the developmental sequence of NPC democracy, intra-party democracy, and socialist democracy. Comparison of the three major democratic institutions suggests that democratic institutions cannot be realized if they violate the reform's bottom line. Only when a democratic institution does not challenge the "red-line area" and the "Four Cardinal Principles", can it be gradually realized. Relative plurality of political support will improve the pertinent regulations for the permanent system of the party congress, but are not sufficient to formally implement the institution.